Let's try this again. Bigger Brakes Cannot Stop You Faster - Bigger Disc Leverage and more

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Here's an interesting little piece of information. The amount of heat released by an average car during a single braking instance from a speed of 90 km/h is enough to boil two liters of water in just three seconds. All stock systems on all cars today are capable of doing this at least 4-5 times before brake fade starts occurring. This means that you can accelerate from 0 to 90 panic brake to a stop then accelerate to 90 again panic brake again and repeat this cycle at least 4 times before the slightest amount of brake fade can be measured. And even once brake fade starts it will be small and gradual and getting your stock brakes to fade to a point where they can't lock up the wheels and trigger ABS is next to impossible. This means that driving on the street cannot overpower the stock braking system. In fact if you ever need multiple panic brakes in a row while driving on public roads than there's something very wrong with your driving.
A lack of braking force does not exist on vehicles. Issue number two is that increasing braking force further cannot reduce your stopping distance.
And this is because your tires are the only thing on your car touching the ground...they are the only point of contact between your vehicle and the road surface. Once your overpower the grip that your tires provide there is nothing else left to overpower. Once the tire locks up and starts sliding increasing the brake force further will achieve nothing. Increasing the brake force via increased leverage or increased clamping force cannot increase the grip of the tires.
Increasing braking force further cannot reduce your stopping distance. And this is because we already have more than enough braking force to lock up the wheels. The comments on my previous video is make it obvious that many people associate brakes primarily with friction and torque....but a much better approach would be to perceive brakes as heat sinks. This is what they do. They convert the motion of the car or kinetic energy into heat and then dissipate this heat into the surrounding air.
Now we're going to compare three different cars to illustrate the extent to which modern cars really don't have an issue with braking.
The first one is the Mclaren Senna which is an 800 horsepower hypercar with absolutely amazing brakes state of the art carbon brakes. It has 390mm discs and 6 piston fixed calipers in the front. It gets from 0 to 100km/h in 2.6 seconds. The second car is the Mazda MX-5 ND has 280mm disc brakes and single piston floating calipers in the front. The 2.0 liter model gets from 0 - 100 km/h in just under 7 seconds. The third car is my very own 2009 Toyota Aygo has 247mm discs and single piston floating calipers in the front. It gets from 0-100 km/h in 14.2 seconds.
So as you can see we have staggering differences in brake systems and acceleration times. But not so much when it comes to braking distances. The Senna manages to come to a stop from a speed of 100kmh in 30 meters. The ND MX-5 manages 33.8 meters. I did a little test with the Aygo and did 10 panic brakes from 100 km/h and I managed an average of 35 meters.
So the McLaren Senna has 57% larger brake discs than the Aygo and has six times the number of caliper pistons. It is also 446% faster from 0 to 60 than the Aygo but it is only 16 % faster from 60 to 0.
So why is this the case? Why doesn't a million dollar hyper car dramatically outbreak a cheap little city car? The reason is that technology has long since reached the sensible limit of braking force.
Getting to a stop from 100 km/h in 35 meters takes less than 3 seconds and this in turn exposes you to forces of nearly 1G. Which is the limit of what the average driver can sustain on their body and still retain full control of their car.
Engineers are more than capable of making vehicles with ridiculous stopping distances. For example the F2004 which is Ferrari's formula 1 car from the 2004 season can come to a stop from 100km/h in just 16 meters. That's more than 2Gs of force. Formula 1 drivers are highly trained athletes capable of taking this load easily. On the other hand 2Gs would make many average drivers loose control of their vehicle. In fact F1 cars can generate as high as 5Gs of force when braking hard from high speeds. That's the sort of deceleration that can make some people pass out.
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#d4a #bbk #brakes

[@theoaglaganian1448]

The dude didn't insult the people who treat him "idiot" while proving his point. Real humility

[@DEATHWISHVQ]

I think the best insult is proving your point to them while not saying any insult because maturity wins harder

[@vale.antoni]

He even gave them them all the possible benefits of the doubt

[@r3uvsgaming]

more maturity than humility imo

[@Fierc3Kid]

This man is a gift to the car community.

[@3UZFE]

He's a proper car enthusiast with an engineering mind. Great that he can make nice videos too!

[@cesarescrignoli442]

He's saving me so much money! 😂

[@oscix]

oh yea definitely he is

[@stfu6397]

For sure

[@Nova-1977]

As a professional race car driver NASCAR breaks are just as critical as acceleration on a paved short track .

[@LichaelMewis]

So in summary larger rotors and calipers can help shed off heat which will help delay or even prevent brake fade under extreme use such as a race track, but they do not decrease stopping distance. Also a video on master cylinder ratios would be nice.

[@andreaslangner6621]

Yes, the tires are the most important thing, but the brakes come right after that.

[@23max232323232323]

Size matters for braking the disc itself, it's a question of leverage, but it's useless as brake power is always higher than the tyre ability to brake. So your car would skid anyway once you overpowered the tyres ability to stop the car. If you have ABS, it'll make no difference. I don't think he mentions that because it would need further explanation. So technically the disc stops better if it's bigger, it wouldn't give any advantage in stopping the car. That's why cars or motorcycles have different brakes at the front and at the rear, they're all calibrated according to weight distribution, tyres, suspensions, etc.. ABS interrupts and reactivates the brakes not to have you car skid, that means brakes are already too powerful, no point in making them more powerful. In racing condition is different, standard brakes are not calibrated to constantly be under pressure, therefore you need something that keeps them at the optimal temperature even if you brake hard all the the time. Whether you do that with bigger brakes or better ventilation, that depends on many factors. E.G.: on motorbikes the front is quite big and has holes for better cooling, on cars the front one can't go beyond a certain size, so it normally has two parts stuck together that lets air flow in between these two parts for cooling purposes.

[@3n3ly7m9]

I only view it as bigger disks means less fade. On my S4 And A4 using oem parts I can go from either 321 mm or the A4 288mm disks to the 360mm D3 and D3 W12 385mm rotors. All in the name of looks.

[@jakub.686]

Yes, bigger brakes will not you stop faster, but make you slow down faster for example from 200-150 km/h where ABS is not involved

[@ruslanvinogradov1792]

you are absolutely wrong cause stock brakes can still easily lock up your wheels even at a 200 km/h so it still makes no difference between stock and bigger brakes. Bigger brakes only have impact when you drive on race track where you have to brake every corner, so your brakes wont overheat as fast@@jakub.686

[@johnsantiago7836]

Great set of videos. I teach high performance driving to many new drivers and we always recommend they save their money by not upgrading to larger brakes (for a couple years at least while they are learning to drive). Pads? Yes. Fluid? Yes. Brake ducts? Yes. All for the same reason: heat management. Want to brake in shorter distance? Upgrade the tires.

[@archangel3237]

Tires and damping control. Better tuned shock absorbers help control weight transfer and can absolutely help decrease stopping distance when tuned PROPERLY for the vehicle and paired with stickier/wider tires

[@johncarey9149]

Many years ago, I was told that THE best performance upgrade you could buy for cars or bikes was fuel, or to put it another way more time behind the wheel, or if you really need it breaking down, improving the driver. A better driver won't use the brakes as often or as much, without sacrificing speed, because they understand the capabilities of their chosen ride. Excellent video as always ... 🙂

[@ukemike1]

@johnsantiago7836 is 100% correct. If your brakes are sufficient to lock up your tires (or engage the anti-lock) then the limiting factor is your tires. All the rest is about heat management. Another unpopular but true thing about brakes... drilled and slotted rotors are a marketing gimmick. With old pads that off-gassed a lot when they overheated drilled and/or slotted rotors helped but they are good for nothing except marketing today.

[@JellyBean-ed2uq]

​@@ukemike1well I had the same opinion, but upon further inspection, it is not the case. Drilled or slotted disks can and will improve braking distance on HARD breaking, just because they self clean better and they gain a tiny cross sectional area that helps them cool a bit faster (not by a lot of course, and this isn't the main reason as to why they are "better" than non drilled ones). You can see an experiment garage 54 did, but we also did some simulations in my engineering school, and yes, just because they can clean themselves better, the callipers can grab the rotors more efficiently without slipping. The gains while kinda small, they are noticeable. Are they worth the extra 80-xxx$ more than the regular ones? Absolutely not, and THAT makes them a marketing gimmick. Do they have some benefits tho? Yes

[@Torchedini]

@@JellyBean-ed2uq But they give cool points. As such, I too fell for slotted rotors.

[@RolandByrd]

Personally, I appreciate the effort you put into explaining things and enjoy your videos.

[@d4a]

Thank you!

[@carmiethompson2676]

👍👍

[@ericstockmann667]

Totally agree

[@stewart8127]

@@d4a the brakes will stop you faster than the tires?

[@bbarnes9544]

​@Trevor Brannon because the would get to hot and fail

[@xxplosiv88]

Remember y'all - this is the man who described what is happening with each "stu-tu-tu" noise in your turbo. You will never beat this final boss

[@ytdood]

which video was that? I'm very intrigued now.

[@griffon2-6]

@@ytdood i second that notion

[@JohnDoe-yi8rn]

@@ytdood it was in boost school

[@Dulc3B00kbyBrant0n]

Has this dude ever tried brembos? They stop more

[@paulsansonetti7410]

@@griffon2-6 kzbin.info/www/bejne/eHe7epqDesRoi6M

[@votive7478]

That was the most genuine “seek help” I’ve seen😂 he really does seem like a cool dude.

[@fredygump5578]

Now I kind of want a video about aftermarket air intakes! That would probably break the internet.

[@asymsolutions]

Simple answer to that is: only do it if your running a vacuum much higher than stock, ooorrrrr you have a car that was gimped by legacy emissions systems like carb and such. Which is not the majority of cars produced in the last 10 years or so.

[@Vincentf30]

Personal experience, If you only do the open air intake without heat shielding you will lose power. If you make it into a cold air intake with heat shielding, you’ll probably still lose power. If you have a turbo or compressor which you have upgraded, then an cold air intake will work. Noticed it myself when the stock new intake was sucked into the box after upgrading a supercharged mini r53 and the car needed a lot more air. In my mind it gave it a bit more torque and made it faster. Never did real tests though but the sucked in airfilter was for me a give away that it’s better to upgrade after putting a lot more horsepower into a car.

[@thatslegit]

@@Vincentf30 all it does is increase throttle response by 1% but if done with a good cold kit it "could" improve top end performance....for about a week. sucking air from the fender is not all bad unless it sucks air from the engine already like a miata

[@azkikr14]

Try Engineering Explained. He did a video on it like a decade ago.

[@zchettaz]

@@thatslegit Its also about smoothness of airflow into the intake - the more the flow is disrupted and bounces around, the more the temperature increases and the less dense it becomes. A differing factor could be the air filter itself and what the type of setup it is (air box/pod filter etc) From personal experience, i had better results with an OTR (over the rail) intake from the manufacturers performance brand (Holden/HSV) in comparison to an aftermarket "cold" intake coming from the fender.

[@psnmadracer27]

Big respect not only for posting a follow up, but for maintaining your professionalism when others couldn't. This is a huge reason why this channel is my #1 when it comes to understanding automotive engineering with the intent of educating others - your commitment to providing content of exceptional quality shows in every video! Keep up the excellent work, and I can't wait for the next one! 👍

[@johngalt1199]

He made another video because he had a serious mistake in the first video @ kzbin.info/www/bejne/eaqrZquFmNiLrtU He showed a cross-section of the tires without considering the other dimension. Skinny and wider tires have the same 2D contact patch area! Google: "discount tire contact patch" for an illustration. Performance vehicles often use wider tires. This does not necessarily increase the size of the contact patch but rather changes its surface shape. Reshaping the contact patch makes it more efficient for accelerating, braking and handling.

[@machtschnell7452]

@@johngalt1199 Most people do not realize this. Of course tire pressure and tire sizes do have some effect. But for proper inflation pressures and similar tire construction it is only the shape, not the actual contact area, which really changes.

[@shawnalbarghouthi4113]

I appreciate that you don’t waste our time with jokes, or with constantly interrupting the video with other stupid and loud clips to make a joke. I appreciate that I can watch it without constantly bringing the volume up and down. And most of all, I appreciate the knowledge and fantastic explanations. Man you’re awesome.

[@M4DesignUSA]

Did you miss the hilarious people sliding on ice??? ;-)

[@23max232323232323]

Agree 100%, there are other channels which are good but too many unhappy jokes, channels with a lot more subs. I don't know if that type of humour appeals to Americans, but to my knowledge that doesn't work in Europe. This guy is from Europe and so am I. I don't find those jokes that funny and there's a time and a place. Following an explanation and hearing puns and cheap sex jokes every 2 minutes makes me want to change video

[@shawnalbarghouthi4113]

@@23max232323232323 absolutely! Once or twice per video is more than enough for an internationally accepted joke

[@JhonIdrovo-the-human]

I started with the same counterpoint of larger = more leverage. But your explanation is one of a PhD haha thank you for sharing the truth and saving me money

[@FrancoPreo]

I fitted larger brakes to my old, pre-ABS car and I can report improved feel and better braking - on the track! Vented and grooved rotors with newer style sliding calipers has made the car far better to drive on the track, but on the street, the difference in driving is negligible. Totally agree with the info in this video

[@stuckinmygarage6220]

You are very good: 1) easy to listen to; 2) enthusiastic; 3) clear presentation of written and visual aids; 4) organized; and 5) 100 % factually correct. Thank you

[@ramadhanisme7]

Sometimes people can't accept the harsh reality 🤣🤣 Btw a brake system series is a great one

[@Zeriel00]

What harsh reality? You're drinking the click bait kool aid if you think your stock break system will be as good as a 3,000K big break kit because this guy says so.

[@killmeh2]

@@Zeriel00 it will for the first 5 minutes on track, next!

[@Logan-dk8of]

@@Zeriel00 guy is really just trying to justify his purchase so he doesn't have buyers remorse anymore. only thing an expensive big brake system is gonna do is look better, have slightly longer lasting pads, and probably last longer for both rotors and calipers

[@warky33]

@@Zeriel00 ok if you know everythjng, please explain how a bigger brake system will stop you quicker when the abs system is already reducing braking force in a panic stop with a stock braking system

[@tanagobg]

​@@Zeriel00 so we should ignore statistics and believe you, got it

[@clark4219]

I thought everyone knew braking distances were determined by the tyres? Oh well, excellent explanation for the physics though! 👍🏼

[@tjroelsma]

Nope, the people who lack knowledge of the laws of physics only look at the size of the brakes, say with full conviction that "bigger is always better" and then call other people dumb for "not understanding how brakes work."

[@jamescaley9942]

Also determined by the driver.

[@joshm3484]

And the brakes, as I discovered when the left rear brake line on my 73 Datsun burst like an old garden hose.

[@rbching3535]

Imo if you can lock your wheels and leave skidmarks then you need better tires. If you do experience brake fade however, only then do you upgrade your pads and rotors.

[@merkel2750]

@@tjroelsma put so 10” wide race tyres on a 1300kg car and you’ll likely see a lack of braking power due to increased tyre grip.

[@FrancoPreo]

I bought a car with Brembos fitted from new, the sort of things people upgrade to. I managed to cook them on the track to the point of having no braking no matter how hard I pushed. Not just brake grade, but brake vanish!! Came home, threw out the rotors and pads and upgraded those. Same brakes, same fluid, but better heat dissipation from the rotor and oars that were more heat tolerant and I now have a car that feels no different to drive, but the more I brake, the better it stops as heat gets into the system. So upgrading the right components, not the whole braking system, is where you’ll get the most benefit. Great video once again, love your stuff!

[@IdiotRace]

My previous car I added a brake kit purely because after a few track sessions I'd have issues with the sliders. Even after rebuilding the calipers, this wasn't the issue with fixed multi pot calipers. I actually got to try the car with the same brake compound in good condition with and without big brakes. I definitely wasn't able to do as many laps before fade but pedal feel was better on the standard setup again like D4A said it messes up the MC ratio somewhat. With the BBK fitted the pedal was definitely slightly mushier, not terribly but enough for you to notice. The fix for it was to switch to a different MC, but while it was worse than the standard setup it wasn't outright dangerous. Funnily enough on the trackday with the standard calipers a lot of people left in the afternoon and the track was very quiet. This meant me doing way more laps than I normally would and out of all the braking components it was the fluid that went first as I had a long session and all of a sudden I went to brake and the pedal pretty much went to the floor. The car still did slow down enough so I let everything cool down and came in. Turns out I'd boiled the fluid (Fresh ATE Superblue when you could still get it) before I'd reached the limits of the pads/discs/calipers. One other benefit was a reduction in unsprung mass that actually improved general feel on the front end as the 4pot wilwoods were much lighter than the standard cast iron slider calipers. Stopping distance however was identical, on track the only thing that noticeably improved braking distances for me was going from a regular summer tyre to an actual track tyre. My current car has a factory Brembo option which I'm going to be fitting instead of an aftermarket kit, it's definitely worse on the unsprung mass side but there won't be any brake bias or MC issues. I may not need this but to be honest after you've had any sort of loss of braking during track driving I'd rather have more safety margin than not.

[@danixsc]

You don't need to upgrade to ride on the streets, that's the point. On track of course you need better heat dissipation, as you're constantly breaking to almost locking, and generating tons of heat in the way. But in the street, unless you're a public danger, you don't need bigger brakes. However, more leverage can lead to a better braking sensation so if that's your objetive, do it. If you just want to brake more, put on wider tires, as i've made in my car, which will also make your car steer better.

[@lucasfrench1841]

Great vid! I 100% agree that big brakes do not mean better stopping. However, I will say that in my specific case they were better. I recently put a big brake kit on my toyota corrolla. I can say, with testing, they do their job better. This vehicle is a track car and while the brakes stopped just fine with performance brake pads, it was a squishy pedal and hard to feel lockups. Not because the brakes were too small, but because the calipers had flex. Through extensive tesing and diagnosis, the caliper flex was the issue. Lots of Bleeding the brakes, replacement master cylinder, caliper rebuilding, still did not reduce the feeling. Then I noticed the calipers had just a bit of flex, less than a milimeter, when brakes were applied. Willwood front 4 piston brakes, BOOM, pedal feels like a normal car. However, they are bigger and now have a differnt piston to master cyl ratio, so I hope I wont be locking up the fronts... Anyways, story over, I'll be testing them at auto X this weekend.

[@d4a]

Good luck! Let us know how it goes. Yes, definitely caliper flex can mess up braking. At the end of the day that's the key issue, brake feel. Because feel and modulation are beyond important for brakes.

[@mannyb8056]

You’ve probably discovered this by now, but fun fact; if your ABS is still operational on your track car, it will still kick in to prevent lock up on your front brakes. This might happen faster than it did with the stock brakes, so be careful and have fun.

[@romb1818]

​@@d4a What about a video about lighter wheels? 🤔

[@nicolosimonetti6369]

It is amazing to see how nervous and rude (to use polite terms) people can become when contradicted; but it is even more surprising to see your patience and kindness in re-explaining the arguments, despite all the insults given by uncivilized people

[@randomguyjustpassingby]

Totally agree. I was expecting something like "to everyone who called me an idiot, apparently you're all idiots" or else. But this coldblooded smart guy is incomparable to those "comment experts". Gentle, tactful, yet accurate and cogent. Love his vids

[@foodaah]

@@randomguyjustpassingby although,i bet some people would find it insulting to be told to seek help because they got worked up over a brake video. there are aways those kind of people that finds problems in any case or circumstance with another person,regardless of the topic.

[@reallyhappenings5597]

Threat responses are never pretty

[@tally5k339]

It's like some of those people vastly overestimate their knowledge on a subject, and don't want to learn if the facts are contradictory. It's their loss though ¯\_(ツ)_/¯

[@kingGar27]

A video about brake bias, master cylinders, etc. would be great 😊

[@Lightdasher360]

Agreed!

[@mr.e8282]

Seconded.

[@tellyfaulkner3466]

Thirded lol

[@tanchonghong3935]

+1

[@Martin_Speed]

Yes!

[@msmeyersmd8]

I've learned more amazing facts about engines and cars from this Man in the last 3-4 years than basic to sophisticated knowledge since I was in my teens. Things that, as an engineering physicist, I should have known. Or figured out on my own. But "motorhead lore" and what seemed to be complicated but "common sense" had polluted my mind. If he says something about motor vehicles, I believe him. And then go back and figure out why I've looked at it wrong for decades. As an aside. I drove big heavy American V-8s from my teens (1974 -1987). Many were used and cheaper models and had front disk brakes and rear drum brakes. Although I started with a disc/disc 1953 Ford Flathead. I don't know if differential brake wear caused me a problem. I lived and went to school in LA for 4 years (1980-1984). To numerous to count times, I would come to partially blind freeway corner at ~65 mph only to see traffic at a dead stop ahead. I would stomp the brakes in my 350 V-8 1973 Monte Carlo. The rear drums would immediately lock up. But not the front discs. The car would end up, what seemed like, 80 degrees sideways with me steering into the turn. Totally in control directionally. Lots of screeching. I could, literally, control the sideways angle of the car by modulating brake pressure. I'd keep it sideways, in total steering control until I was pretty certain I would stop and gradually let off on the brakes. First slowly, and then immediately, it would snap back to straight forward. I was never trained at all in this type of driving. I just happened a lot in LA back then. The horrors of the 55 mph days. Going 55 mph on a LA freeway would get you killed. Many of you trained drivers are probably saying, duh? It happened often enough and was so amazing to me that I developed skills in using that technique. My previous cars were also heavy only with drum/drum brakes. This never happened with them. Obviously before ABS systems, did this mean that the proportioning valve was not correct or out of adjustment? Could I have corrected it to make rear lockup less likely? My personal observation is that a front heavy V-8 car stopped faster when controllably traveling sideways? Am I incorrect about this? I've always been leery of front disc/rear drum brake cars since then. Comments and thoughts are welcome. After that, I bought a used 1973 350 Corvette Convertible with front and rear discs plus 4 wheel independant suspension. Life was Grand. When I was 25 years old. Just Graduated Med School. I learned what a "women magnet" car really was. It was "chick magnet" back then. But I didn't want to offend any Karen's who police KZbin for micro aggressions. Only one more personal anecdote and a question. I promise. From 1982-1986, I also occasionally drove my girlfriends early 80s Toyota Tercel 4 cylinder low power and light weight 4 door. Narrow skinny tires on ~14" or less, steel rims. All factory parts. Not a "hotrod" car or one that inspired spirited driving ever. That car spun itself ( my interpretation) or I spun it >360 degrees on ~ 5 occasions. Always at normal driving speed. Every time, the road was coated with a wet watery mist on top of a normaly dry oily road surface. Never touched the brakes until it was out of control. I guess this is why F1 drivers get the Big Bucks? My first front wheel drive car, I realized that just letting off the throttle in a normal speed wide sweeping turn simulated only putting on the front brakes. The opposite of a RWD car. Instantly Initiating the out of control spin. I was lucky as no other traffic was ever around. An instant lesson in oversteer. I believe it was a dangerous vehicle. I've driven many later 1980s FWD cars without any problems. Any ideas on what was done to rectify this vehicle based design problem? Before ABS, traction control, etc.?

[@Bad_handle]

You sir have consistently been my favorite automotive KZbinr for like 5 years. I seriously think you’re the best. Thank you

[@MrAPCProductions]

Definitely make the video of piston size vs master size ratios.

[@fastinradfordable]

I put a larger master And it was excellent improvement. Even such that when the reservoir is bone dry there is enough fluid in the cylinder for full-braking.

[@kilianortmann9979]

@@fastinradfordable I hope you have also increased the area of your pistons accordingly. Otherwise you now have less brake pressure than before.

[@cornishcat11]

@@kilianortmann9979 wrong

[@kilianortmann9979]

@@cornishcat11 Please elaborate. Pressure is the same at Master cylinder and Brake Pistons. Thus force is proportional to inverse Area. Increase piston area increase brake force, increased Master cylinder area decreases brake force.

[@DylanL69]

@@kilianortmann9979 no the master is SMALLER then the caliper

[@ApexAdvisor126]

Thanks for spreading truth. It just shares how few people actually understand how cars actually work. They get so excited by modifying thier car, they stop using common sense.

[@dooby1445]

I wouldn't really caulk this up to common sense. First thought of "how to stop faster" is "oh the brakes stop you, so bigger brakes must be better at stopping you".

[@apex107lrp]

Using "common sense" is usually the first, best way to get something (you know nothing about) all wrong.

[@ApexAdvisor126]

@@apex107lrp Not if you know how to look at something critically. Shows most folks can't use critical thinking skills.

[@Brandon_Tyr]

@@ApexAdvisor126 If that were true engineering degrees wouldnt take years.

[@ApexAdvisor126]

@@Brandon_Tyr The time it takes to understand something and the thinking process to understand it are mutually exclusive. You can understand something new every day and take years to master the topic.

[@vitoraugustocarlos3758]

I can say this guy is absolutely right and I speak from "experience". I play Automation the car company game and a misconception I used to have was "stronger, bigger brakes = shortest stopping distance". My cars used to have 6 piston brakes with high quality sports tires and every time I drove my cars, it felt like the car wasn't stopping properly compared to the BeamNG cars. Then I looked at one of the graphs in Automation and realized that my brakes for example had 12000 newtons of force compared to a 8000 newton grip limit of the tires. I had to reduce the braking power so it was closer to the tires' grip limit and guess what? My cars were actually braking properly. The tires dictate how much power you send to the ground and how well you stop (of course, depending on the surface you're on). Use slick tires on ice? You're not going anywhere because your tires have no grip. And the guy at 0:42 who commented that F1 cars and trucks have huge brakes forgot two details: 1) F1 cars have slick tires, you know, the tires with the insanest amount of grip on dry roads. Of course those can be used along with carbon ceramic brakes because those slicks have the grip to handle the carbon brakes. And since F1 cars don't have ABS, we see the tires locking up sometimes, because the brake force was higher than the tire grip. 2) Friction force = µ • N. Y'all remember this equation. The higher the normal force, the higher the friction force. Trucks are heavy, so they have high normal force and thus, higher friction force on the tires, which justifies them having huge brakes. And they need those brakes because you want those 50 tons of cargo to stop quickly in an emergency, don't you agree?

[@Florin_Bolocan]

Brilliant video! Spot on! I’ve been an Automotive Engineer for the past 14years, most of that time being in Brakes Engineering, working for Renault, Ricardo UK, Bosch Engineering and recently I moved to Jaguar Land Rover and I can confirm that ‘bigger’ brakes will only do one think, in the vast majority of cases, they will disturb the brake feel and the modulation as the brakes will tend to lockup faster as you very well stated in this video. Also if they are aftermarket brakes don’t be surprised if they are ‘noisy’. Unless you are racing, I wouldn’t even touch the stock brakes. We spend years getting the system sized correctly and the adequate pedal feel. More importantly most of the stock brakes are quiet, because of a very good reason we literally spend over two years in Brakes Refinement testing by making sure that the brakes are quiet, many millions of pounds are spent in that respect. With aftermarket brakes you cannot have the same level of Brakes Refinement as the aftermarket doesn’t have access to the same level of dyno, CAE and vehicle testing as an OEM does. Most of the braking systems are oversized anyway, as most OEMs design the braking system around the AMS test, which is not even a legislative requirement. The AMS test is extremely severe (10 consecutive brake stops from 100kph to 0) and it’s not a realistic use case. Consequently we end up with very big brakes and more importantly very heavy brakes. Therefore do yourself a favour and unless you are racing and you need the thermal capacity, then do not waste your money on shinny new ‘big’ brakes.

[@antonio94]

I don't think AMS test is extremely severe. Imagine going down a mountain road. You might keep the brakes engaged for a lot of the trip going down. Would really suck if the brakes start to fade. Also imagine the brakes aren't brand new, but on a 20 year old car, that was maintained by an average person, and that doesn't really care about fanatic maintenance. Most people do maintenance on brakes only when weird sound appear, especially on older cars.

[@schrodingersmechanic7622]

Towards the end I can definitely say that the single best performance part I've ever bought for a car were lighter wheels. Lower unsprung weight dramatically improves handling and lower rotating mass has an exponential effect on acceleration and braking at higher speeds. At legal speeds though it doesn't make much difference.

[@briank10101]

Should help with comfort too over high frequency bumps provided one doesn't have overly stiff springs and dampers.

[@Patrick-zr8tv]

This actually helps with fuel efficiency in urban areas a lot too. A lot of energy, therefore power and fuel, is spent on rotating the wheels instead of accelerating the car when you are accelerating. If you remove much of that weight you aren't going to use as much energy to spin the wheels up to speed. This has a compounding effect the faster you go.

[@jacksin3323]

That makes a lot of sense. Thats why magnesium wheels are more desireable? Is aluminum lighter than magnesium? I know magnesium ones are more expensive. Man this stuff is deep. I love learning about it. It helps with figuring out all my builds.

[@vedranbitcoin2827]

Best car mod I done is switch from 195mm wheels to 215mm. It does not sould like big change but improvement in handling is hudge.

[@kevinburke6743]

The main rotating masses on a car, apart from brake rotors, wheels & tyres. Is: The Engine, clutch, flywheel, transmission/gearbox, Propshaft, diff & driveshafts!

[@michaelcoppola9266]

Love your work. Love how you deal with people who have no idea. Please keep doing what you do. I really enjoy your videos.

[@albertoecharri921]

I came across youyr channel a few weeks ago and i have to say, it is just what i need. Someone who obviously knows what he is talking about and presents it logically. we really need more people who think like this, look at the world and dont feel, but try and contrast. I love it, keep it up. It makes me really think. I love it. I love you, and its amaizing. Thanks Im a fan!!

[@ThatGuy-rf8de]

In my personal experience with performance vehicles, I've only ever upgraded the brakes on one vehicle. And I didn't go with bigger brakes, I just went from steel to carbon ceramic. The vehicle is a 2011 F150 5.0L, and I have quite a bit of work done to it. One of the first things I did to the truck was better tires, it has 305/50/r20 Nitto NT555RII. Even with those wide, grippy tires, the factory brakes could still lock the wheels up. I changed to carbon ceramic mainly for the decrease in brake dust. With all that being said, I am slightly tempted to get a big brake kit, solely for one reason. My truck has 650 horsepower, so when I try to brake launch, the engine overpowers the brakes. I also think a big brake kit could be useful on a large lifted truck, since they run significantly larger tires than stock.

[@andrigtmiller]

I would love to hear about the master cylinder to brake caliper ratios. Love these videos.

[@erui2848]

yes plsss

[@JohnDoe-yi8rn]

Yes

[@westmus]

That's basic physics/math. The difference in bore size vs piston sizes give leverage and multiply the force coming from the pedal. The pedal on its own do also multiply the force that's made by the foot

[@xuevgermanist]

Yeah, bring it on!

[@alexwhite407]

yeah that would be an interesting topic.

[@Ragas07]

The first part and this video changed my perspective towards the ideas I had on what would improve the braking performance on a streetcar. Thank you. Appreciate your efforts on creating such high quality content

[@reddyfreddy]

they wont stop you faster once.... but on the track, bigger brakes will stop you faster more than once.

[@briank10101]

@@reddyfreddy like after brake application number 5 from 200 kph to 0 kph in a row in 3 minutes

[@hotflashfoto]

It makes perfect sense. I'd like to see a video where you teach us how tire width changes the braking distances and how they affect cornering.

[@i90r]

I would add "and a grip on the snow etc"

[@cosmic_cupcake]

we definitely need a video on tyre width and it`s effects on grip, especially. There seem to be many missconceptions floating around.

[@frederickevans4113]

I put urethane control arm bushings on my 1998 Camry, upgraded the steel 14-inch wheels to 16-inch Lexus ES330 wheels, and put wider, lower profile tires on the car. The tire size was carefully calculated to maintain the same outer diameter and circumference to about half a percent, IIRC. With that, I also kept the stock front brake calipers and rotor diameter, but upgraded to drilled & slotted discs sandwiched between ceramic brake pads. Later I ditched the rear drum brakes (5S-FE 4-cylinder) and installed the rear disc brakes from a V6 Camry of the same model year. Acceleration with that 130 HP 4-banger was "meh", but the car cornered and stopped quite well (even with a loaded trailer).

[@jimlyon7276]

Being a biker, too much tyre width on the front just screws up the steering. Which leads me to also favouring a softer compound for the front tyre.

[@RakeshGuptak]

I learn a lot of new stuff every time I watch your videos. Thanks for the time and effort!

[@d4a]

Thank you for the support, I sincerely appreciate it

[@podulox]

[@ApexAdvisor126]

Do the brake bias video please! That would be fun to learn about

[@dizzywow]

It's pretty obvious, really. The forward weight transfer while braking means that the front tires have more traction and can take more braking force. The master cylinder applies more hydraulic force to the front. If all wheels got the same, the rear wheels would lock up (bad) while the fronts are not yet achieving maximum braking potential.

[@inorite4553]

Screw that! He should do a video on why my brakes get "Ring around the rotor" on spanking new pads/rotors on stock 4 pot Bremboa

[@tavarisjones551]

Big brake kits will typically improve your brake feel and ability to modulate the brakes. People confuse this with "better" or "stronger" brakes. Like you said, the tire stops the car, not the brakes. Stock brakes have enough grip to lock up the tires. That is all the brake you need. Anything beyond that is all about brake feel, or ability to dissipate heat for repeated high speed stops (like track use).

[@henrytang2203]

Think you nailed it. Bigger brakes allow for more brake durability during track use - because of brake fad. So you can still stop at the limits of your tyres when brakes pads are working at 50%.

[@angelgjr1999]

Stronger brakes are overrated, all it does is lock up your wheels faster. But they are handy (they don’t overheat as fast) if you’re slowing down from very high speeds. :)

[@xorbe2]

@@angelgjr1999 Completely backwards, weaker brakes tend to lock-up after reaching a certain point. Stronger brakes when set up properly allow better modulation and control.

[@starydwumas7481]

And they last longer due to bigger pieces of materials, force put through bigger area. Like for my brake pads I pay 10$ and they last damn a lot.

[@Squashed8Ball]

@@xorbe2 no, Angel is completely correct! As is this video.

[@ln5185]

I am stunned by this video. I always had this curiosity but never searched for an answer. Thank you for doing this clip. Wow

[@JoeyVilleneuve]

This is a great video! I've had this conversation with so many people. Tires are more important to stopping than brakes, especially on a sports car. I only upgraded my brakes on my RX-7 once I improved my driving skills to surpass what my tire/brake set-up could handle. I upped the tires to a track tire, and then upgraded the brakes to match the upped grip. I didn't go BBK though, I only upgraded pads and discs to slotted.

[@rokyc]

I have to say, you are giving by far THE BEST explanations on mechanic and physic topics on youtube! So easy to understand with real word comparisons. Keep up the good work, you have a new fan and subscriber from Ljubljana. Svaka čast jarane!

[@ema1671]

I thought your last video was very well done. This one is superb.

[@jaypikachu6660]

Wow, even I am a 30 years Certified Master Mechanic, I learn something new today, thanks.

[@cjeevs]

Great to see such a detailed explanation. Good on you.

[@samoopsd]

Would love to see more videos in how braking systems work and how to calculate brake bias/ hydraulics etc!

[@justiceibezim4590]

100

[@Taso10000]

Yes please!!!

[@dimm__]

+1

[@thesentry5710]

I would love to see a video on brake bias and other little brake system quirks like that :) It really sucks to see how negative people can get in the comments of your videos, you've been extremely informative, and I guess people sometimes take it personally when it turns out their mods were not that well thought out, this video was a very good response though.

[@carlstrohm3785]

But damn they look good stopping the same! 😉

[@the-next-gear3626]

Thank you for putting this video out there for those car enthusiast who believe they know more than the engineers who designed them. Your video is well explained. Jason on Engineering explained has covered this as well. Thank you both for educating the community properly. Coming from an engineer in the automotive industry that specializes braking systems.

[@influentialgurning]

This video had just the right amount of emotion. I was deeply moved by the attempts at the philosiphy of science and admonitions of reports of physical observations following the blind faith that (what just so happens to be evermore hegemonic) legislation is the guarantee of positive and desirable material effects in the devices manufactured in adherence to coercive manipulation by whim of bureaucracy, and I'm sure the UN loves me too. One may ask, however, where were the bureaucrats forty-ish years ago, when, apparently, brakes weren't sufficient to brake properly. One may then ask if reliance upon the autocracy that is the wont of bureaucracy is the best method of ensuring effective engineering is achieved to a customer's satisfaction. If one finds oneself answering these enquiries by saying 'society' more than any other thing, or at all, one might want to have another pop at thinking about it. In so far as any technical requirement is desirable, communicable and achievable, we can define its parameters and metrics. In so far as a body wielding power identifies those correct parameters and expresses an intent to impose them, we have merely been advised that, should we, in our manufacturing endeavours, fail to display the qualities stated as requirements, we shall suffer some form of restriction or sanction, ultimately by force. We must remain vigilant to all aspects of the application of this force. Regardless of the level of empirical accuracy and rigour that form the basis of a statist claim to its entitlement to act, we must first examine the moral legitimacy of the claim itself. If the state's claim is not ethical, it has no grounds to proceed, and its scientific references relating to its remedy are rendered moot. We, thereupon as by default, must continue to be left at perfect liberty to find our own solutions without the usurpatious use of force. The state becomes more secure in the grip and expansion of its operation with each strangulation of our independence. It will, therefore, respond with endless cures to the phantom demands that it generates in our name, and then call this democracy. It relies on the fear of a population by that same population, and, in the case of braking efficiency, for example, it can appear to be effecting the only method for the population's peace and harmony. It leaves us to neurotically detect, at its hysterical direction, increasingly ethereal and mysterious harms and risks in each other, and turn on anyone who says, "That is not so, and, what is more, I have caused no harm, my existence is not to be valued as a quantum of risk, and it is my business." When any code is written to provide a newfangled sense of security without which mankind cannot proceed, the population will soon forget what the state allowed before, what the people can do and did without the state, and how easily the state forgives itself when it decides it couldn't be bothered to provide what it promised. To put it less laboriously: When overwhelming power is the means by which you are granted performance, comfort or sustenance, whether you wanted more or could live with less, you will get only what you are given. Do we live eventually as men, or permanently as children? If, as will ultimately be demanded, we give up all power to a centralised system of management in exchange for what is sold as Expertly apportioned provision, succour and safety, what may we demand of brakes, cars or food when we are finally told we deserve none? How do we retain control of effects upon products, and expression of our true demands? Is it by restricting our voices to simply saying (in a style of our preference), "Check the code," while pointing to remote, brute authority and directing our fellow man to submit? Unfortunately, I didn't manage to see the title subject being addressed, as what is, today, loosely classed as an advert appeared before the suggested exposition had arrived, and, obviously, I would never watch what is, today, loosely classed as an advert.

[@VujaDeGaming]

I definitely want to see a comprehensive video on upgrading a brake system the right way. Seeing the ratios and what would actually increase performance. I am looking to upgrade my brakes, but have no reason to as of yet. I intend to do light track driving and would upgrade instead of replacing my brakes which are running about 10k miles from their end of life.

[@robertquandt5511]

Brake pads. Maybe slotted or vented rotors but not really worth it if you are doing light track days; just getting some track pads on new stock rotors will do wonders (if you need them properly).

[@CP110]

what you want to do is dissapate heat from repeated high speed braking. So things that manage heat better are brake pad compound, rotors with higher vent count (maybe a bit thicker as well), brake ducting, high quality high temp brake fluid. Now to take advantage of ur clamping force you need more traction, I.e a well setup suspension and proper tires.

[@houssamalucad753]

If you do track driving bigger brakes might be beneficial to counteract brake fade by achieving better heat decapitation, also they look cool 🤷🏻‍♂️

[@MiggsRacing]

If your doing track days get some high heat dot 3-4 brake fluid in the system, put the stainless steel braided brake lines if you’d like, there not always needed, go get your self a set of pads meant to handle the heat and abuse for a race track when you get the right pad you will stop incredibly faster than you thought your stock brake system could handle. I recommend ether getting the brake rotors lathed so there fresh for a new pad, or get a set of nice slotted rotors to help give a better bite into the brakes,

[@MiggsRacing]

Upgrade your stuff in stages, your car is like a science experiment on the track, if you go and upgrade the tires and the suspension and then everything else all at once how will you ever know if your modifications actually made you faster on that track, star off by upgrading your brakes, if you notice that your out performing the tires then upgrade the tires, then you might find your out performing the sway bars upgrade those, but don’t do everything at once.

[@mugenfoo]

Anytime anyone is able to brake hard enough to cause the ABS to kick in, that means the car's theoretical limit of braking ability (for a given tyre size & particular road surface) has been achieved. ;) 15:45 at this video sends a very good warning as well. Fully second this. Always choose a good aftermarket BBK from a reputable mfg that makes a specific kit for your chassis. Universal mix-n-match brake system are best reserved for ground-up track car builds.

[@WentzCraft]

A video describing an argument I've had it dozen times. And everyone telling you the bigger breaks are better have bald tires. You're the man liked and subscribed.

[@jeremycole-baker2799]

I'm amazed that people disagreed with this. I've had various old cars with over the years and none lacked brake force (although some required a lot more pedal force to lock up the wheels). Example, a 1956 Morris Minor with tiny 6" drums all around and no brake booster... They were regarded as very average brakes even in their day, but you could lock up all 4 wheels no problem even with modern tires. The problem with the small drum brakes was overheating due to poor heat dissipation, and also uneven lockup and poor control in panic braking situations, not lack of brake force.

[@Albertosalat]

Would be nice to have a video about brake bias depending on the weight distribution on the car

[@vaerxxx3231]

Too much braking force in the rear may cause locking of only rear wheels and loss of vehicle control (Oversteer.) Typical bias is front because of vehicle momentum shifting forward whilst braking.

[@geluix69]

almost all front engine cars are 70-30% the ABS module can vary this to zero rear and 100 front depending on many factors.

[@MarianoLu]

The issue about a video on brake bias is that it can never be objective.

[@adamfreeman3000]

@@vaerxxx3231 Yes there is weight transfer under braking but how much weight transfer is dependent on some vehicle physical attributes (such as the height of the CoG above the ground, weight distribution etc) but crucially weight transfer is also dependent on the rate of deceleration. Higher rate of decel will result in more weight transfer. And now it gets tricky because there are countless factors that can effect grip and thus peak deceleration (tyres, wet/dry road, weight etc). So in reality it is impossible for any passive brake system to achieve an optimum brake bias for all conditions. The result is vehicle manufacturers tend to opt for a 'safe' brake bias (i.e. forwards bias) because as you say, a overly rearwards bias would be like pulling up the handbrake every time you brake hard and that is definitely NOT the way to make a car fast.... However, since all manufacturers go for a very 'safe' brake balance, there is often performance to be found by shifting the brake bias marginally rearwards (e.g. by installing rear pads that have a slightly higher friction coefficient than the front pads). This will shift the brake bias rearwards towards a more 'neutral' brake balance which will reduce stopping distances. The tradeoff being the rear of the car will become slightly more unstable during braking.... A 5-10% shift REARWARDS in brake bias however is still very controllable for even a moderately skilled driver and could even further improve lap times by helping the car rotate on the brakes during corner entry.

[@gaborb]

@@adamfreeman3000 small corrections/notes factory brakes can also lock the rear wheels so no gain in stopping distance. Lap times might be improved as usually 'racers' like more oversteering behaviour. (Which is not really 'neutral' :) ) abs also does brake force distribution so it is not only hardware

[@theevilwitchtheband]

Hard work you've gotten into trying to explain not so simple concepts to uneducated crowd... one of the best channels around for sure!!

[@yaroslavbozhdynsky]

That's literally what education is for. Problems start when some people are immune to knowledge.

[@zoebooth8545]

I ended up on this video trying to figure out how my 37“ mudding tires work on pavement 😹 I learned so much and this was wonderfully done! Thank you for touching on the importance of learning your car stock first 😭 it makes everything so much easier!

[@bavaria2k2]

This channel is an absolute GOLD MINE to the world of automotive enthusiasts...

[@donchaput8278]

Great Video! Track stuff is fun but the best reason brake upgrades is definitely TOWING. I upgraded our tow vehicle for just that reason. Quality vented/drilled rotors made a noticeable difference when trailering in the hills/mountains where you use your brakes a lot.

[@FrmerK20]

Very true. There you really see what heat does to the ability to brake

[@str8xrippin]

Yea but that's completely different and its exactly what he was explaining that bigger brakes are just larger heat sinks. Here you are not comparing stopping distance or power but the performance to reliably do that without fatigue. That's why you go for big brakes

[@alivdee9946]

You could consider an engine brake to prevent overheating your normal brakes (just like big trucks have) In hilly and mountainous terrain your engine is your primary brake source. Maybe a bit more difficult with an automatic tranmission.

[@CapablePimento]

Ive had brake fade down a steep hill, and its terrifying. Also a good reason to learn how to use gearing and engine braking. If you had to drop in to a lower gear to climb it, you need a lower gear to descend it on the other side.

[@donchaput8278]

@@str8xrippin It's actually directly related. Drilled and slotted rotors allow for gas venting and additional air flow to help with heat dissipation. Rather than adding more weight and brake equipment you can get better performance by going with better rotors. If you need a really serious brake upgrade for towing you probably want to examine your tow vehicle and probably go bigger. I was towing at max capacity for my Ford Freestar so the rotor upgrade was the most I needed, the next step would be getting a truck.

[@bodevaughn1599]

Man it made me so man every time a car reviewer slams the brakes on a nice car and goes "man these are nice brakes" then goes to talk about the brake rotor size. THANK YOU for helping put the right information out there even if some people are actively arguing with you.

[@angus3963]

Best video yet! Personally, all I've ever done is steel braided lines for pedal feel and knowing they're new, nice sticky tyres (I'm partial to Nitto Invos), and Carbotech XP8 pads with a friction coefficient of ~0.58-0.60, you're avg brake pad typically have a friction coefficient of ~0.3-0.4. With that setup you'll need to relearn all your braking points and thresholds otherwise you'll be stopping way farther away then you expect! 😆

[@webn8]

This is very interesting, and makes a lot of sense.... I'm probably a slight exception in that my project car is almost 50 years old, and came with pretty horrible brakes. However, the first upgrade to the brakes I did was to swap 1985 small truck disks onto my 1975 compact car. This worked very well, but in the interest of reducing weight, I eventually swapped the stock truck brakes for a light weight "big brake" kit. This did reduce weight significantly, but didn't seem to change braking all that much. However, the only time I've lost control on the track (1/4 mile drag strip) was when running skinny front tires and hitting the brakes hard (trying not to break out while bracket racing). Thankfully I recovered before crashing, but it was indeed the front tires and not the brakes that limited my braking ability in that case. Brakes as a heatsink is a good thing to remember.

[@pnwtree]

yes! we want those videos about brake master cyls and brake balance plz!!

[@MarvinRB3]

Seriously good job on this. You managed to turn a contentious and quite hostile topic into something constructive and informative.

[@loukas371]

Great video, I think the best explanation I have seen for this phenomenon. A lot of people struggle to grasp this. Also talking some sensibility about upgrades...

[@NeoIsrafil]

Tires and then suspension are generally going to be your biggest inprovements to braking time. Once youve improved the tires though, you add more traction, and thus it CAN help to improve the brakes (more pistons or more leverage or both). It CAN help. It probably wont in many cases, but hell, it wont generally hurt much of anything to my recollection, and a lot of the better quality brake kits, and pads, and such have better brake fade characteristics under heated conditions. (See also racing) Another thing you should take into account, if you throw on 20s or something ridiculous onto your small car youre adding a lot of extra rotational energy to those tires, and thus it is often worth it to throw in better brakes to handle it.

[@str8xrippin]

Some people live on a different earth with different physics I see, thanks for your 100% spot on explanation I really enjoy all your videos, I was binge watching your whole channel so looking forward to more content

[@jozsefizsak]

Fantastically clear and articulate explanations of these phenomena. It's a joy to watch a video that doesn't require figuring out the intended meaning in real time, even if that might be an excellent brain exercise, likely quite useful for fending off dementia! Thank yo so much for this fine work.

[@HenrikMyrhaug]

You are absolutely right about this, your brakes don't stop your car, they stop your wheels from spinning. What stops the car is the friction between the wheels and the road, and the maximum friction you will get to the road is when you are using barely not enough force to lock up the wheels. Once the wheels lock up, they start to slip, and friction is drastically reduced, so once your brakes are strong enough to lock up your wheels, making them stronger will not increase the friction to the road, and hence will not improve stopping distance. Just a nitpick however, Gs are a measure of acceleration, not force. One G means 9,81m/s^2, which means you accelerate/decelerate at the same rate as gravity.

[@fatosvraja]

Thank you for this very educativ explanation❤ Rock on

[@rolfingkarting]

Loved the video. What most people probably experience is that their new brakes bite harder after "upgrading", which hopefully feels nice, but does nothing to reduce braking distance at the tire limit. I also wanted to add that even for track day use, all you need is brake pads and fluid designed for track use. Because they work at higher temperatures, and maintain brake force even after repeated stops. Brake caliper and rotor upgrades may look nice, but sometimes actually alter the brake bias front to rear. This may or may not be beneficial depending on what tires you use, and how you prefer to drive into corners. And BTW, upgrading brake calipers and rotors and then still mounting street-type brake pads gets you nowhere for track use. It is really the pads, fluid and cooling that makes a big difference, not calipers and rotors. Unfortunately most brake pads designed for track use do not work well on the street, so you end up having to swap back and forth. Carbon ceramic brakes may be an exception to this.

[@stevesamuel263]

Carbon ceramics are bad for track use, they fail quickly when exposed to excessive heat. But they're perfect for street driving, no brake dust and last forever

[@patrickneyman6739]

you hit on something there. a more intense bite is a negative on breaking performance, as it reduces ability to modulate the brakes. those who find that increased bite to be an advantage likely are terrible at using brakes in any performance situation

[@Thumper33333333]

​@@stevesamuel263 Don't forget they are ridiculously expensive. No one is tracking carbon ceramic rotors without having a trust fund or rich sponsor. Replacements are thousands of dollars.

[@edbo10]

if you have a japanese car dixcel makes some really good pads rated for both street and track use, but they are definitely not cheap even when not including shipping. dixcel z-type pads, bought them for my car after i had a bit of brake fade after some fairly hard mountain runs. these things can brake all day, but they do emit a lot of dust.

[@REgamesplayer]

New breaks decrease braking distance. You start going into nuances which author of the video did not went. He talked about ABS, but omitted to tell you how ABS INCREASE braking distance. That is only natural, because they keep on releasing brakes during braking. And why you are concerned about emergency braking distance? Better brakes will no doubt decrease distance it takes to brake due to tire lockout, but it will come at a severe trade off of braking control. Either way, a skillful driver can replace ABS by just being good by simply disengaging brakes himself when he need to shift directions.

[@umeng2002]

Good explanation on clearing things up. I think a lot of people were thinking about the theoretical model of just increasing braking force instead of the application of bringing an actual vehicle to a stop faster.

[@vallanhtkd]

This has been illuminating! I'd love to hear more about brake bias and ask the other stuff you mentioned!

[@akdomun]

I think it makes sense that bigger/better brakes can stop your car more consistently after repeated stops. But outright brake distance will depend more on your tires. Very good analysis!

[@eyemastervideo]

You are correct. Bigger brakes will not make you stop faster. The limiting factor is the traction your tires give you. It's pretty simple. However, at the track, you only need bigger brakes because small brakes will heat up faster and then become dangerous as they lose their braking power, and other things can happen too, like boiled fuild and such...

[@Phrew]

Not only will they be more reliable on track, they will also allow for less exhausting braking, due to the increased leverage and clamping force. But down the line every brake setup is capable of overcoming tyre traction.

[@netts2315]

This all was covered in the first video about this he made.

[@eyemastervideo]

@@netts2315 Yes I know, yet people missed the point :(

[@Phrew]

@@netts2315 And yet, here we are, in a second video that had to explain the same thing again.

[@netts2315]

@@Phrew Well to be fair this video touched up more about stuff not presented in the original. My question was that wouldn't upgrading brakes matter once you upgrade the tires to have enough grip to not be able to lock up on stock brakes, and the answer is yes.

[@leon8847]

Id love a detailed vid on Brake Bias, Master Cylinders etc. Keep on going

[@whipwhop2617]

Haha, I'd hate to be one of the people who tried to call you out. So grateful to have someone who can share their in depth knowledge with the world :D

[@xrex7839]

Really love your way of explaining, I was shocked when you said people in your comments thought bigger brakes helped stopping distance "under normal road use"

[@AriKolbeinsson]

One thing that many miss is that massive, ultra powerful brakes also increase the unsprung mass of the car, possibly leading to worse suspension. (tyre+rim weight will, of course, have a bigger effect, but this is something many people don't think about) I was going to mention the brake feel aspect, but of course the video went into that! And yes please: videos on brake bias and all that other good stuff

[@raoulrr]

Usually the stock single piston floating calipers on most vehicles are made of cast iron, while the fixed caliper multi-piston setups that most enthusiasts use for brake upgrades are made of aluminum, so usually brake upgrade mods get you unsprung mass weight savings. I have upgraded the brakes on my Mk7 GTI because it's my track car, and the stock floating calipers are perfect for street driving, but would overheat and fade after a couple of laps on a short track where the lack of long straights cannot cool them down between corners, especially when running on sticky track tires. The upgraded calipers (Audi TTS, fixed 4-piston aluminum calipers) even with the larger discs are about 40% lighter than the stock calipers & discs setup, plus the fixed calipers give a much better brake feel than floating calipers ever could, especially at the limit. Again, this is a track car setup, for street driving it would 100% be a waste, just like D4A says.

[@4bidn1]

This.. I'm part of a car club for a specific vehicle model and in the early days of the club (early 00's) everyone was doing the "big brake upgrade" of pulling the bigger rotors and callipers from the sedan model and putting them onto the coupe model, but over the years it's become common knowledge that new oem coupe setups out-brake the sedan setups in every scenario, they were just made well enough that the heat dissipation advantages of the bigger rotors and callipers were completely negligible compared to the disadvantages of the unsprung mass increase even in track situations. So the only way to get better brake performance is to splash out on track specific systems that are lighter, which are few and far between for 25 year old Mitsubishis.. This really clicked for me when I went from 6.5" alloy to 8" steel wheels as a teenager.. I figured wider = wider tyres = more grip = better performance but in reality on a car that weighs less than 900kg (1900ish lbs) the 8" wheels were *that* much heavier that there was basically 0 performance increase. Currently sitting on a much lighter set of 8" alloys and the difference is crazy. Now the limiting factor is that the stock seats dont hold me straight enough to corner any harder lmao

[@mr.e8282]

Not only would larger breaks negatively effect the sprung/unsprung ratio, giving worse teaction, & actually negatively effecting breaking distance.. and everything else your suspension does, then there's also the spinning mass consideration. Anything spinning on a car has to be accelerated twice. Once to turn it, & again to move it forward. Twice as much energy is expended in moving a spinning part. Meaning that 1lbs of weight reduction on a spinning part is worth 2 lbs anywhere else on the car. Between that & the unsprung ratio, this is why lighter wheels is such an important modification in sports applications. This is true, of course, not only for accelerating the part, but also for decelerating it. More force is required to stop a spinning part than a fixed one.

[@operator0]

Unsprung, ROTATIONAL mass. Which is the worst kind of weight on a vehicle.

[@ConnorwithanO]

@@mr.e8282 It's even worse than that! The angular moment of inertia for the brake rotors will increase with the square of diameter, i.e. doubling the diameter will quadruple the momentum needed to spin it to the same RPM. So a rotating part takes 2 times the energy to move as a non-rotating part, TIMES the square of the diameter!

[@AxianMapping]

I seriously can not thank you enough for how much you have helped me with understanding cars over the years. You alongside with Engineering Explained have incredibly informative videos, that are short, brief and straight to the point, I'll be it with some skits here and there but that's always fine :). If you were to read this, I would recommend doing some videos on race/street suspension, how it works and how it could be improved. Also, maybe more videos on rotary engine dynamics? Could be both interesting choices, just a recommendation though! Have a great day/night!

[@SoulTouchMusic93]

he's store brand jason from EE. great guys, both of them!

[@593432223]

This is so true d4a and ee ate the best

[@thenewhalogod]

EE is incorrect so often that I unsubbed. He uses "math" to 'prove' incorrect positions. Take the hydrogen fuel video from a while ago. "Oh, the fuel tank volume of a GTR gives the car 50mi range" GREAT its designed for a DIFFRENT FUEL. No shit its not optimized for hydrogen, its designed for gasoline. The hell does that prove? Li-ion is 0.08kwh/L and hydrogen is 1.1kwh/L(@500bar, not unheard of. Can go up to 2.3kwh/L) So all battery cars are invalid? He argues that hydrogen cars are mathematically impossible, and while BEVs are less than hydrogen. What a shill and a clown.

[@GregoryVeizades]

@@thenewhalogod Glad i'm not alone. Guy annoys the fuck out of me.

[@thesushifiend]

And Unlike EE, this guy doesn't have the voice of Kermit The Frog, which makes his points much easier to follow.

[@svang1991]

You’re a gift. Please continue doing what you do.

[@needsmoreboosters4264]

The TL;DR is that if your brakes are capable of locking up with the tires you're using, they have more than enough force. You can't stop faster without increasing grip. Big brakes are primarily for fighting brake fade from overheating due to heavy, repeated use. There's one sort-of-exception: if you switch a car on stock brakes to racing tires, the stock brakes might no longer be enough to lock up with the increased grip, meaning you do need more force from the brakes themselves.

[@michaelblacktree]

Good video. Another thing to consider is that bigger brakes will often increase unsprung weight. And that has a negative impact on handling. Because of that, I would only use bigger brakes if absolutely necessary.

[@spartancrown]

This is true and it often times is offset by much lighter aftermarket wheels. The overall weight though may still increase depending on the size of said wheel tire combo.

[@polsal69]

Very good point!

[@johngalt97]

@@spartancrown I'll take adequate, lighter brakes *and* lighter wheels FTW.

[@jurekgadzinowski2895]

I do not know how to call it proffesionally because English is not my 1st language, but the good thing you can do is to change your rotors to the ventilated ones of the same size as you had before. They will overheat less easily and weigh the same.

[@jurekgadzinowski2895]

@@johngalt97 Agree, just look at the F1 in 2021 or 2020 vs now. Bigger wheels are slower.

[@flyonbyya]

Brakes get me super emotional !!😂

[@stephenboitoult8774]

Love this!!!! I've been telling people for years that just because you CAN do some mod or other, it doesn't mean you SHOULD! However, though you touched on it lightly, I think you need to consider that quite a lot of your audience (including, emphatically, myself) do NOT drive relatively modern cars with ABS and huge wheels that can accomodate huge discs. Some of us (NOT me, thankfully) may even be struggling with all drum brakes on 2 tons of 60s Americana with upwards of 400 BHP on tap (yes they really did sell such death traps!) My own case and that of many of my friends in the same boat (and the same car!) is similar, but not the same. We are cursed with a love of the 70s built Triumph Dolomite. It weighs around 1000kg, has 13" wheels and comes with a range of engines between a 58bhp 1300cc and a 127bhp 2000cc. But no matter what engine you have, you get the same 8.5" (216mm) solid front brake discs. Along with fixed, twin 48mm piston calipers. These are fine on the small engined models but totally inadequate for the HO cars, especially when tuned as well. The problem isn't necessarily size, per se, but as you said, it's heat dispersal (or lack of) and the fade that goes with it. The cure I and others have adopted is to retrofit the car with vented discs. These are slightly larger at 239mm (1" larger overall) and carry a 54mm single piston floating caliper, which are the biggest that can physically fit under the stock wheels, but the main point isn't the size but the heat dispersing capability of the vents Vs the original solid discs. The conversion is known well around the owners club and has no detractors. Over 150 kits have been sold which is pretty good when surviving cars number less than 1000 in ALL models. And whilst one person's experience is not, as you so rightly say, a statistical universe, 150 people are a step in the right direction! And we think that, in this case, with this particular type and model of car, that we DO actually know better than the OE manufacturer. The car stops a wee bit better, but more importantly, fade (which was always the biggest problem) has been completely eliminated, even under track conditions!

[@mazzen79]

This guy is a gift for us all...! Congrats!

[@krisbodurov1497]

I agree with what you are saying. Once i increased the power of my stock engine to nearly double, on day to day driving around town i did not need a big brake updated. However once i started driving on track, i found out that after the 3/4th lap my stock brakes gave up and. my next investment was bigger brakes and disks which helped on track, but yet again on day to day driving i cannot see i massive increase in stopping in town with the bigger brakes.

[@Rondo2ooo]

Nowadays I just service my motorbikes by myself, yet I am still a petrol head. Your channel is definitely one of the best in taking time and delving very 'rationally' into the details. Learning or refreshing knowledge. Thanks for your great work!

[@nigelcox1451]

Firstly, thank you for the wonderful refresher of the technology I learnt at college, nearly 50 years ago. Right from the start I was thinking 'heat dissipation' and tyres' grip. The original 'classic' Mini had drum brakes, always capable of stopping the wheels turning if properly maintained. The upgrade to discs (from the Cooper versions) was unnecessary unless used for competition. The later fitment of discs by Rover was to remove the need for adjustment of the drums every 3000 miles, not for any additional braking effort. I must however take you to task. The most important feature of any car in amking it safer, is the driver. Sadly, that is the most difficult part to improve, so we go with ABS, EBA, etc.

[@TradeWorks_Construction]

Thank you for the follow up video. I think you did a much better job, addressing why you won’t experience a big improvement by upgrading your brakes. Out of all the channels you are my absolute favorite for breaking down these normally controversial topics into very simple, straightforward concepts and data. I think a lot of people would have to just be ignorant or denial to argue otherwise

[@mattrondeau7466]

If your current brake setup can lock the wheels up or induce ABS, you have reached the maximum capability for that vehicle. You cannot exceed maximum. It doesn't matter if your discs are 4 ft. in diameter, you can't clamp down harder than maximum.

[@1DEADBEEF1]

Great point! Max is max - can't go beyond that!

[@inorite4553]

Once you reach max level, you stop leveling up

[@potatopobobot4231]

No

[@mattrondeau7466]

@@potatopobobot4231 Perfect screen name for you.

[@andreastiglio9958]

the "oil" part of the braking system is so often overlooked, it would be interesting to see a video about that!

[@octavianfie5918]

The laws of physics are the only ones one cannot break. They say: as long as the braking system is able to stop the wheels from turning, which is the case for all cars out there, “stock” or not, the only limitation to the braking force & hence distance is the tyres’ grip. Sticky, warm, broad tyres are the only ones which’ll do the trick, nothing else. Well done, mate, keep it up! 👍

[@axelriet]

Except that it’s not. Take any showroom car, drive it to top speed, slam the brakes and the ABS won’t kick in. By the time half the speed has been scrubbed the brakes will be so hot they start fading already and the ABS never kicks in.

[@iaahner]

100000% correct all around. The one thing I will say is that what you mention at 18:46 is a bigger deal than you let on. Sometimes a lighter brake with more mechanical advantage allows a skilled driver to better modulate brake during threshold braking, and it allows them to eek out that last 1% of tire capability better. Very minor difference, but on the track it starts to make a big difference. Also if it reduces driver fatigue, it can help lap after lap, much the same as the thermal considerations you mentioned.(turns out yet again, the loose nut behind the wheel tends to be the limiting factor...) Fantastic video! Well stated all around.

[@derherr65]

The only missed common exception I can think of is when oversized aftermarket tires are added. Many 4x4 guys are familiar with this. Going from, for example, stock 30" diameter tires on a jeep to 37" tires CAN be a large enough change to exceed the stock caliper's capability. It also is HIGHLY noticeable on acceleration! In this case the additional power of bigger brakes may be necessary, as well as a re-gear to regain some semblance of acceleration, because you have far exceeded the original design parameters.

[@TheCarpenterUnion]

That's again because you've added cross sectional area on the tire, but yes I think due to the added rotational mass the "factory" requirement for the size would be larger

[@DaveXL495]

My 4WD has upsized tyres (diameter, width, and heavier duty construction) and additional weight in modifications (bar work, batteries, drawers etc). I definitely found it hard to lock up the brakes on high traction surfaces until I upgraded the brakes to a larger diameter (318-338mm).

[@carlos11111926]

That's wrong... Even if you oversize like that your tires... Brakes have enough torque to lock rotation. Don't forget that what's in contact with the road is like a little line... Bigger tires doesn't mean bigger grip in the road. So... At the same speed... Bigger tires mean that the rotation of the tire is smaller. So... The brake's still capable of locking completely the tires... 🎉

[@leorousselet2910]

@@carlos11111926 Wrong. Tire radius is directly correlated to the amount of torque needed to lock the tyre. Torque necessary to lock wheel = Tyre radius * Weight on tyre under dynamic condition Increasing the tyre radius makes it harder to lock the wheels because of the increased leverage (therefore increased inertia). It has nothing to do with the grip of your tyre.

[@carlos11111926]

@@leorousselet2910 Yes, but the factor is not enough to create a real problem. The brakes on a car are designed to block the rotation really very easily...It's almost impossible to mount wheels on a car that will cause the brakes to no longer block the rotation... It would be to say that the brakes have been badly developed.

[@25aspooner]

I would definitely like to see more brake videos. Thank you for the awesome content!

[@kenselleck2414]

Yes please! hydraulic ratios, Brake bias, and proportioning (and metering) valve videos!

[@younessibndaouia7399]

I don't know what to say, i appreciate your work, good quality content.

[@peanutbutterjellyjam2179]

A major point you missed here is that upgraded brakes look cool, hence, better stopping distances.😉 Good job, D4A. Looking forward to your next video.❤

[@abitoffcenter383]

Plus how much better it runs and handles.........after a wash 😁

[@camberwellcarrot7524]

Adds more horsepower than a turbo.

[@kontrarien5721]

Red ones stop better.

[@4bidn1]

Don't forget, every JDM sticker added to the rear window is an extra +25hp

[@FrostyNut]

🤣

[@Ak3rn0]

I absolutely need more of this on brake ratios, master cylinders, and everything you know about it

[@03shigginbotham]

really appreciate the time you take to explain, and the respect that you afford to others in you response to criticism.

[@302ci1968]

I totally agree with you. My Golf R had very good brakes with no much fade. I changed the pads for slightly more aggresive ones and the disc (keeping the same diameter and same undrilled discs, but with better heat dissipation). It didn't brake better. It could just keep braking at high speeds (very high, actually, on autobahns) a bit longer. And when I swapped my 18" wheels with michelin pilotsport in 225 width for 19" with michelin pilot supersport in 235, i just notice a very little difference in favor of the wider tyres. So, to summarize, i didn't notice a significant difference, except by keepin the fade a bit in control.

[@chucknastydjbitchfit5317]

Yes, I want to see a video about master cylinders and piston ratios. Please and thank you. Excellent video. I learned a lot from part 1 and now part 2 of this brake vs tire debate.

[@panthergaming2856]

Please make a video on brake bias and piston ratios

[@maroimage]

Awesome content overall!

[@d4a]

Thank you so much! Highly appreciated

[@oditeomnes]

I just swapped half defective, worn out shock absorbers with a brand new set. Now the new suspension forces the tires to stay more in contact with the terrain instead of leaving it to the springs to uncontrollably bounce around. I definitely think upgraded and if you are serious, adjustable suspension will give you more control for your money both in accelaration, cornering and braking.