Weight has no effect on your car's top speed! | Know it All with Jason Cammisa | Ep. 09

Adding extra weight to your car will slow acceleration, but won't reduce its top speed. In determining a car's top speed, its engine battles two main forces: rolling resistance and aerodynamic drag.
At very high speeds, air resistance makes up the vast majority of the overall drag on your car. So much so that an increase in rolling resistance from extra weight is likely negligible.
Adding weight may increase your car's rolling resistance, but it's also usually offset by a decrease in wind resistance because the weight compresses the suspension, which in turn decreases the car's frontal area and, typically, its drag coefficient too.
So in some cases, your car may be even faster when fully loaded - at least on level ground. The extra weight will increase top speed going downhill, but decrease it going uphill.
But be careful of things that seem like they'd be related. Like, don't believe someone when they say the only sure way to make it rain is to wash your car. Because no matter how much it seems to be true, it's not.
Oh, but your car might require less stopping distance when fully loaded. See? Sometimes things are related in the most unexpected of ways.
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[@DenisKudlik]

knew that, still watched. can't miss a discount adam sandler short film

[@psalmco2425]

I already know a lot of what he says in these videos bcuz of engineering explained but I watch anyway cuz Adam Sandler makes it funny hahahhaha

[@visakhrajendran741]

@@psalmco2425 Indeed. Jason Fenske is professor who explains everything whereas Jason Cammisa is more of visiting lecturer who makes the lectures more interesting and at the end of lecture you can catch him doing burnouts in the parking lot 🤣 He might even skip the lecture for hands on approach. 🤫

[@psalmco2425]

@@visakhrajendran741 Well said! And only now did I realize they share the name Jason Hahahhahah

[@tonya.2645]

Somebody cast Jason in a movie please. He'd be funnier and more likable than Sandler.

[@cavalryman_s197]

Slash Ryan Reynolds.

[@claysmell]

50 in a school zone - that was brilliant

[@iZai53]

The last statement is undeniable. 100% true.

[@JohnYayaJr]

And regrettably, so is the first statement about vanilla flavoring.

[@memememine1]

Just like how the fastest way to get the light to change is to swap your glasses for your sun glasses or vice versa.

[@shoaibmanhas]

Now I can relate to this.

[@RafitoOoO]

Just as the easiest way to make your bus arrive is lighting a cigarette lol

[@richardbixler]

No! That last statement was totally false. Everybody knows washing your car makes birds poop and trees begin to excrete sap and mushy fruit.

[@titaniummechanism3214]

This felt almost like a video from Engineering Explained, but without any whiteboards.

[@JasonCammisa]

But with even MORE Jason!

[@visakhrajendran741]

@@JasonCammisa Um? You mean Adam Sandler? 😏

[@OOICU812]

And about 20 min shorter.

[@pic18f452]

I'll take this over engineering explained. I respect the other guy but his high pitch voice is a bit too much for me.

[@EliasTheHunter]

@@pic18f452 your loss.

[@Serps-ii9zc]

Land Speed racers will actually add weight to their cars in strategic places to aid traction on the loose surfaces they race on (dry lake beds). That second gen Camaro Freiburger has gone 260 in is like 5,000 lbs.

[@Adamas_83]

Having walked around and sat in that Camaro I can attest it's a heavy girl.

[@Josef8080]

That is the down force

[@prandomable]

extra weight will only slow down your acceleration because heavier objects will require more force to move it. It's better to shift weight, and NOT to add unnecessary extra weight.

[@prandomable]

Weight is never a good thing (for racing). Only time weight would help is if you are topped out and driving (down hill). Weight will actually help you pickup and increase MORE top speed due to gravity. Weight could make your vehicle more stable at high speeds. Weight sucks for acceleration. Weight sucks will still affect your top speed a little bit. Weight sucks for cornering. Weight will make you go up hill MUCH SLOWER.

[@prandomable]

Weight will STILL affect your top speed significantly in some extreme cases though. When your vehicle is towing a fully loaded trailer you can NEVER reach your original top speed. Semis towing a fully loaded cargo trailer can NEVER reach its original top speed anymore compared to when the Semis NOT even towing a trailer... It is possible for Semis to go 100 MPH on flat level ground (when not towing). But NOT possible to go 100 MPH anymore (for sure) on flat level ground when towing the cargo trailer with full load of weight.

[@TheCarKrazeOfficial]

This is my favorite host on KZbin 💯 Jason explains everything so well

[@Hagerty]

Thank you for your kind words!

[@esnebta]

That's because it's watered down and applied specifically.

[@prandomable]

@@Hagerty Sir. Weight will still affect top speed. If you added too much weight. Think of putting BIG heavy rocks on your remote controlled car...your RC truck would be much slower...

[@prandomable]

​@@Hagerty if weight doesn't affect top speed. Try towing a 5,000 lb trailer on flat level ground and try to find out lol....

[@johnmichaeltwist5086]

​@Hagerty 0:30 - 0:40 next time provide the formulas, or at least sources where the statements are taken from. Power is Force times Velocity, if you divide this by weight which is also units of Force, then you get Velocity, not acceleration: FV/F= V.

[@shadowboy813]

Correction: It takes 8 times as much power to double your speed. The force of aerodynamic drag increases with the square of speed, so the amount of work (force times distance) done increases by 4 when you double your speed. But power is work divided by time (or equivalently, force times velocity). And at double the speed, you do that work in half the time (or exert 4 times the force at twice the speed). That means it takes 8 times as much power. Drag goes with the square of speed, but power needed increases with the cube of speed. This is why it only takes a typical car about 70hp or so to go 100mph but you need ~550-600 to go 200mph.

[@braziliansheetbox2497]

That means a bugatti chiron 300+ only needs 23,4hp to go 75mp/h

[@bourbonyoung6237]

And? The topic was weight.

[@jakubkrcma]

@@braziliansheetbox2497Not exactly because you need to consider the changes in rolling resistance too. But approx. yes. Maintaining a relatively low speed requires very little power.

[@jakubkrcma]

@@bourbonyoung6237When there is a mistake in the video, it is perfectly OK to correct it. And I would like to add that at supersonic speeds, this is one power higher. You need 16 times more power to do 4000 mph than 2000 mph! 😱

[@denmark219]

Whoever at Hagerty hired Jason deserves a massive raise. I absolutely love his content. BTW I use Hagerty for my classic boat insurance.

[@lesterscrugs2272]

Always fun to hear Jason break stuff down. Very good decision by Hagerty to give him a platform.

[@richardnunes8499]

Jason, I'm sending this to two of my buddies that don't believe this when I tell them. Great, informative video! Thanks

[@memememine1]

I wish more people would test drag. I had an SS 1LE (455hp) and although it was somewhat quick from 0-100 mph it would hit a brick wall at around 110 mph. I traded it recently for a base 911 Carrera with 350hp. The 911 is slower below about 85 mph. But once you get past around 100mph the 911 pulls even and then slightly ahead and will actually do the run from 110-160mph slightly quicker than the Camaro with 105 more horsepower.

[@bingoberra18]

I just never looked that good in a dress tbh

[@vettekid3326]

The amount of drag is everything. That's why my old C4 Corvette with only 245 HP but has a drag coefficient of 0.34 will still go 155 easily. The same engine and gearing in a Camaro of the same vintage will only do around 135.

[@Way2EasyDIY]

​@@bingoberra18lmao

[@Maverick8t88]

I look forward to these Know It All videos so very much.

[@ramongomez7380]

Once again you nailed it!! Jason you are amazing dude 👍

[@btolley100]

Love this guys work. More please!

[@mr22guy]

Great take on this. Please do a video on forged Pistons. I'm so sick of people crapping on cast or hypereutectic pistons and saying forged is the only way to go, when they have an unfavorable expansion rate and really are unnecessary in a naturally aspirated engine.

[@addertooth1]

Hypereutectic pistons are more "brittle" and susceptible to cracking from pre-ignition. On a well tuned car of moderate performance this is not a risk, on higher "energy density engines" like the 2ZZ-GE (which uses hypereutectic pistons with a MMC coated bore), it IS an issue. This has led performance tuners for that engine to refer to it as a "glass engine". Google: "2zz-ge glass engine" for more details. So, if you are tuning at the ragged edge where pre-ignition can occur, you want pistons which can better accept abuse without cracking. This is why forged pistons are frequently sought out for higher end performance engines which are producing maximum power. On my 2ZZ-GE (supercharged), I have limited myself to no more than 2.5 HP per Cubic Inch. The tune is not as radical as it could be, if my pistons were forged.

[@Robert_iii]

Love me some Griots Speed Shine. Thanks for the always entertaining quick hits in between your long form pieces.

[@BWGPEI]

It's so much fun watching / listening to you. I guess that watching this will make the thunderstorms appear and force me to shut down this computer, grin.

[@Chrismayn]

Congratulations on the weight loss Mr Cammisa!!! ❤️💋❤️

[@jonathandv81]

Love the facts, and also waiting for you to do special video on the Rimac Nevera, they just put another nail into the coffin for super car combustion engines.

[@WhiteMouse77]

Once in TG, not sure if Clarcson or May explained how many HP Veyron needs to reach 300KPH and how many to continue accelerating to top speed....the numbers were mindblowing...

[@left_ventricle]

For some people who might wonder whether this is same for airplanes, it kinda is. Aircraft drag is concieved from two; lift-induced and parasite. When we are talking the aero drag for the car it means parasite drag, which increases as the speed rises. However the lift-induced drag works the other way. It increases as the weight of an aircraft rises, often by significant margin especially for smaller wing aircrafts. But at speeds it’s so minor - just like rolling resistance - that it won’t have too huge of an impact. But that only goes for internal loads, not for external loads. For example, if an aircraft for whatever reason has to have some weaponary or pods of sort, the parasite drag would be significantly increased, especially around mach number 1.00 due to huge increase in wave drag. So to summarise: Increase in weight does not significantly decrease top speed of vehicles, as long as all the loads are internal, not external. This goes for cars, motorcycles, aeroplanes. However I know next to nothing about boats.

[@dazone]

waving at someone at 50 at a school zone! 😂😂😂 you won!

[@tymwalt]

As a beagle owner, I appreciate that clip.

[@nichopaulu8395]

Good video, as usual. It's that last statement that gets me thinking... Hmmm...

[@jaroslavkalivoda3496]

in 100 years of those episodes i will be quite educated about my car Thanks Sandler

[@MustafaAli-85]

Question is .. how the heck it's the first time for me to see this channel ! Kool video

[@jasonshull3106]

Love it. Mr Jason.

[@shiftinggears9842]

Hopefully Jason Continues to do know it all! Also proper care or feeding of cars . Goos stuff and also comical

[@haulngrassracing]

Like waving your hand at 50 mph… in a school zone 🤣

[@ashtonlewis8580]

I would like to suggest a correction at 1:10. Aero drag does increase with the square of speed. Since drag x speed = power, aero power increases with the cube of speed. If speed doubles the power requirement increases 8 times. I do enjoy your presentations.

[@geemy9675]

100% that's a big difference. lets say you want to beat some land speed record and go 10x faster than your road car. you need 1000x the power, not 100x ! well off course noone's going to attempt land speed record with the body of a road car...I guess BTW work(energy) = force(drag) x distance meaning the range/mileage loss when you increase speed is "only" speed squared. more realistically, you drive 10% faster, you are using 33% more power and reducing your range by ~17% you should get pretty close results with evs, but ICE will get different results because efficiency varies quite a lot with rpms and load

[@geemy9675]

also I'm wondering if loading your car ( usually in the back) will really improve drag. unless you have some self levelling air suspension, you're also upsetting the pitch ? any way any gain in flat top speed willl be payed dearly uphill anyway

[@NOBODY-hj6qd]

@geemy yes it would improve the drag

[@campbellwilson4019]

Keep it coming Jason

[@blackmagick]

1:01 The only drag at 50 in a school zone would be the force of your license getting suspended.

[@chuckgrenci6404]

Additionally, once you get that mass moving, fuel mileage also isn't affected much either.

[@jodeb0014]

Rolling resistance coefficient * Normal force(newton) = rolling Resistance(Newton) 0.02 (dry asphalt and car tire) * 14730 N (Normal force of a car that weights 1500 kg) = 294.6 N highway speed = 27 m/s (Force*distance)/time = force(N) * speed(m/s) = power(watt) 27 * 294.6 = 7954.2 watt = 8 Kw Thermal efficiency of engine = 25% Actual power = 8/0.25 = 32 Kw 32 Kw draw for 1 hour = 32 Kwh 32 Kwh = 3.62 L of gasoline Distance traveled at 27 m/s for 1 hour = 97.2 km Fuel used due to rolling resistance economy = L/km = 3.62/97.2 = 3.72 l/100 km Conclusion: It does matter

[@joonanissinen9207]

@@jodeb0014 how did you get 3.62/97.72=3.72?

[@bingoberra18]

@@joonanissinen9207 (3,62/97,72)*100. Thats where the /100km comes from.

[@jldude84]

On flat ground, yes.

[@ansgaryeysymontt7155]

@@jodeb0014 Your math is way off reality.

[@johnspence2630]

You had to mention where vanilla favor came from huh lol, still I'm a fan of Jason. Better than most on KZbin.

[@danziger69]

Funny and accurate. Thanks, Jason!

[@terryorcutt8739]

Very interesting!

[@e28forever30]

Nice backdrop, an E28 and an E30, the icons from the eighties.👍

[@colbysciarrilla4325]

About time someone clears this up. Nobody ever believes me.

[@doca8792]

Never knew this. It explains why I still hit 120mph in my Scirocco on the 118fwy back in ‘87 with a buddy passenger and two chicks in the back seat at 3am.

[@agustincmb5404]

This are really cool. But I’ve seen videos of people reducing weight and breaking in less distance. Id love to see that video

[@oaguilera81]

LOL Jason is a great comedian 😂

[@chienfuzan]

Is it just me that feel smarter after I watch this? Thanks for the intimation.

[@cirian75]

don't forget to drop your tires pressures back to normal after you've not longer got the heavy load, my car's rear end is sketchy AF in fast corners when its just me in it and heavy load pressures

[@patrickposey2003]

Jason is the best auto journalist in life.

[@Stroporez]

Nice!!

[@devandrasimanjuntak1646]

thank you for this! I remember there’s this one guy I talked to who said I was delusional when I said weight doesn’t affect a car’s top speed. I even gave him some examples, like how the A45 AMG has the same top speed as an Ariel Atom V8 despite having 130 hp less. But he just dismissed it as meaningless. Jeez…

[@YeahBass3k]

It's because it does affect the top speed. This video is wrong. He's just approximating because it's small levels of influence, but it DOES affect the actual resulting speed.

[@YeahBass3k]

He is also wrong with his last statement on "car mass doesn't affect stopping distance".

[@addertooth1]

@@YeahBass3k It is complicated. There are so many other unconstrained variables in that statement. But, as mass goes up, so does the tire pressure on the ground (due to gravity). This is why F1 cars make use of downforce (which presses the tires down to the surface) to increase cornering and braking grip. Yes, the harder you press a tire down, the MORE braking you "can" get. But then you also have to consider what "treadwear" (softness) the rubber of the tires are. Softer tires wear out quicker, especially when the car is heavier. Either way, the numbers involve a lot of variables which must be considered to get a holistic answer. All I know is that my flyweight Lotus Elise with 30 treadwear tires seems to out-brake virtually all other cars at the track. I can start breaking later before a corner and get down to the same speed for the corner. I don't touch the brakes at the "1" or "2" marker before the corner, and always start braking after the "3" mark. There is no "4" marker at the track.

[@Cartier_specialist]

Mind blown 💣

[@VeluzM]

I applaud the drag race reference.

[@kenxiong6830]

Power, gearing, and aerodynamics

[@wakjob961]

Nothing more true than that last statement.

[@dhoyt902]

'Reads title' , Sigh, let's see how pedantic we can get about this today.

[@Electrilyfe]

Yeah gearing ratios is also another huge factor in top speed.

[@bingoberra18]

Errr how does increasing weight not affect braking distance? When braking you get a weight transfer forward. You might mathematically try to convince me that the friction coefficient is constant and that more load increases the grip on those tires linearly. But that is not the case, the tires are actually working on a curve and if you put most of the weight on the front that will overload those tires, and that is force dependant, so the more weight you have shifting forward, the easier to overload the tires. The point of a racecar having a low CGH is to minimize that weight transfer, and keep all tires as evenly loaded as possible.

[@somat111]

Up to a point extra weight in the trunk may help as there'd be less nose dive and the rear brakes may not lock up as easily so can contribute more to the slowing process? I'm curious as to the explanation tho.

[@Briguy288]

You're right, I think extra weight would increase braking distance. Tire load sensitivity is the explanation for why increasing weight doesn't linearly increase grip. Hence why heavier cars, even with tight body control, have worse lateral G's.

[@alanjenkins1508]

More weight would increase friction of the tires, both before and after lock up. However there is more kinetic energy to dissipate and there is a limit on brake efficiency. Don't know which one will win out.

[@andrealves2210]

I think you should prove your point by testing it!!! that would be epic!!!

[@sketchpv3080]

Mind boggling indeed! But not as mind boggling as extra weight not increasing braking distance. I’ll have to check the math in that one!

[@oscwede]

any idea how that works? I was curious too

[@reedhoward27]

@@oscwede Braking distance is directly proportional to braking acceleration (Ba). Ba = Force of friction (Ff) / Mass (m) Ff = Coeffecient of friction (u) • Normal force (Fn) Fn = m • Gravity (g) Ba = u • m • g / m Ba = u • g Since "m" doesn't appear in "Ba = u • g", the mass of the vehicle doesn't affect Ba, and therefore doesn't affect brakng distance (in theory). ( "•" means multiply)

[@prandomable]

More weight typically will still increase braking distance. Heavier object is harder to stop. The reason why more weight will offset braking distance is because more weight also means MORE TRACTION on the braking tires...can you grasp this concept?

[@BigUriel]

@@prandomable The problem is that tyres can only handle so much heat, if we assume tyres are "indestructible" then weight doesn't matter, in real life if you put a ton of weight on a car it will increase the braking distance because as soon as you step on the brakes the shear forces cause the outer layer of rubber to heat up very quickly and start to shear off decreasing the friction coefficient. Bigger tyres fix this, not by having a larger contact patch (which they don't, contact patch is a function of tyre pressure and weight), but by having more rubber on the outer layer so the heat generated is spread over more material so the tyre surface doesn't get as hot. Same reason why bigger tyres give you more traction in acceleration and cornering. This also assumes a single braking event from a reasonable speed. In multiple braking events or braking from a very high speed then the heat dissipation of the brakes themselves also become a limiting factor, heavier cars need bigger brakes also to prevent them from getting too hot.

[@prandomable]

@@BigUriel heavier vehicles are harder to stop correct. More weight means more momentum and more inertia.

[@howardlevy4345]

More Jason!

[@Siva.P.S]

We need to test this inside hyperloop tunnel 😜

[@jeep13ca]

I want to hear your reasoning behind claiming that increasing weight will cause the car to stop shorter. Unless you have amazing brakes and amazing tires and take advantage of increased mechanical grip from the tires due to the weight. As the conventional thinking is that the brake power required to stop a vehicle varies directly with its weight and the “square” of its speed. For example, if weight is doubled, stopping power must be doubled to stop in the same distance. If speed is doubled, stopping power must be increased four times to stop in the same distance.

[@nolan122]

yep, its def wrong. The equation is pretty simple, a=F/m

[@RadDadisRad]

Caster oil, also found in raspberry flavor as well.

[@markusdahmann4107]

I do really like the explanations and try not to miss a single video. This time I do not totally agree though. Perhaps You can solve the puzzle: auto motor und sport (German leading car magazine) tested in the 70s loaded versus unloaded vehicles. Accelaeration went down significantly which may be caused by rather faint engine power (Golfs had 75 bhp at that time in "S" ...). But top speed suffered also. Unloaded 166 for the Golf S became a mere 155 with full load. Well - there is the change in aerodynamics which is far more severe in these days than it is now - maybe? And the relatively ,ow speeds mean that rolling resistance remains rather important because aero takes the all important lead at speeds at 200 and above (km/h). What's the key to this effect - which occured on Benzes as well as on Fords and Opels .... ?

[@Mladjasmilic]

1:13 Going 2x faster needs 4x force. But, as you have 2x speed and 4x force, and power is speed x force, then POWER must go 8x. That is why even small 20hp car can go 100km/h, but to get to 200, you must have at least 100hp. It was also why 400hp cars can reach 300km/h, but you need 1000hp for over 400.

[@arekb5951]

You need 800hp to go from 150 to 300km/h in the same time as 100hp car with the same aero resistance goes from 0 to 150km/h (obviously not taking tyre slip, energy losses etc. while launching into account). If you take aero drag and rolling resistance out of the equation, you can go 1000km/h with a 20hp engine, it will just accelerate slower and slower as the speed goes up (you need more RPM to speed up, but to keep the same HP value you will have to decrease torque). So the statement saying that you need 4x the power to go 2x the speed is true, it will just take more time to go from 1x speed to 2x speed than it takes to go from 0 speed to 1x speed.

[@Mladjasmilic]

@@arekb5951 I do not understand you.

[@macaron3141592653]

"waving at someone at 50 ... at a school zone" lmfao

[@BryanHoefer]

Question I'd like some advice on. How does tire pressure relate to tire size? I just downsized the wheels on my Veloster N from 19x8 factory performance pack wheels to 18x8 Enkei wheels. Dropped close to 10lb per corner. I went from a 235/35 to a 235/40 tire. Factory pressure is 38F/ 35 R. Would you keep the same pressure with the larger sidewall?

[@TheLouisianan]

I know this is an old comment, but your sidewall's size makes no difference. What you're concerned about is the size of the contact patch; imagine your car is parked on a giant glass plate like a glass coffee table and you can see from below. The spots your wheels sit would look like black rectangles and that's the contact patch which is all tread. In your case, if you have the same tire width, then you'd be safe to just keep the factory pressures listed inside your door.

[@mmmarcd]

This is a fact that gets a lot of new pilots as well. Your cruise speeds do not change with weight.

[@jacquesgouws]

South Africa represent @ 1:36 :)

[@Zenkilove]

I watched it once, was surpised. Watched it later a Second time forgetting that i watched it already, deja-vu and: oh watched it already. Half a year later: watched it a third time, already forgott that i watched it 2 Times. But These Videos are so good, we need new ones 🎉

[@moflyboyblanquito541]

Damn I used to have that kind of car behind you. That car was what enlightened me to power to west.

[@visakhrajendran741]

😂 Yep I check the weather and see it is nice and sunny outside so I wash my car. 2 days later thunderstorm warning.😆 Everytime. I am curious about the braking distance episode btw. When can I expect it? 😀

[@pascutia]

Jason’s E30😍😍

[@donaldpowers3314]

It will get there but will take longer . It effects my car at the drag strip. So top speed at the track it effected. But in my PICK UP. A FEW HUNDRED lbs. Will aid with it in get going the (launch) by stopping tire spin. At the start

[@robertelmo7736]

That's not TOP Speed at the track...that's TRAP speed. Top speed is when you hold it down and it won't go any faster.

[@donaldpowers3314]

@@robertelmo7736 top speed for 1/4...at 125mph.. dugh... theres always a .....

[@theangelking96]

I follow this channel just because of Cammisa

[@JasonCammisa]

@Cold As The Poles It was - now I'm seeing Dollar Store Ryan Reynolds. Just when I got my mom to stop saying "You don't look like Adam Sandler!" 😂

[@sarahdell4042]

My Delica has a 5-10 mph top speed hit when fully loaded for camping, with passengers.

[@sofielee4122]

In racing, is the induced drag from having a massive wing on your car considered to be less important than the resultant increase in stability from having all that downforce?

[@kensmechanicalaffair]

Cars that actually need a wing usually have enough power to overcome that bit of drag. Better to stay planted to the track.

[@Nozerone]

The last bit about braking is true. You should be more worried about an empty semi-truck stopping in time than a fully loaded one. Now while an empty semi will usually weigh around 30k with the trailer, this weight is basically nothing with how large and how hard the tires are. With out a load on the trailer, the grip the truck has is nothing compared to when fully loaded. Since your ability to brake is dependent on the grip you have with your tires, a fully loaded truck has more grip and thus can stop easier than an empty truck. Sometimes you can see the difference between unloaded and loaded, if you've ever been behind an empty trailer and see white smoke as the wheels lock up while they are slowing down for a light. You'll never see that happen with a loaded trailer unless they are braking really hard in an emergency. Also, keep in mind that it takes about 3 football fields for a loaded truck to come to a stop from 70, and empty is even longer. So if you ever decide to cut off a truck, then suddenly have to slam on the brakes. It's not going to be a question of if the truck can stop, but instead a question of how far the truck is going to drag you before it stops. In emergency braking situation, you WILL out brake the truck by a very large margin.

[@dbeckMSP]

please do a video on the braking distance comment. I can't wrap my head around that.

[@MSBELK]

That's cause its mostly wrong, having more mass does mean you can dump energy faster (because of better grip) , BUT at the cost of having MORE energy to dump, its a multi variable problem and my guess is you wpnt dump all your energy in a shorter time if you have more weight since the gain in grip is inferior to the loss in weight-gain

[@MSBELK]

2:55 having more mass does mean you can dump energy faster (because of better grip) , BUT at the cost of having MORE energy to dump, its a multi variable problem and my guess is you wont dump all of your energy in a shorter time if you have more weight since i the gain in grip is inferior to the loss in weight-gain

[@GraveUypo]

in extreme cases it isn't. like my dune buggy. it has no weight on the front wheels, literally under 100kg. it needs a ballast to give the front wheels grip otherwise it's so floaty you can't go faster than 50kph if you want any sort of control over it.

[@paulturner6071]

@@GraveUypo extreme cases isn’t a 1500 pound dune buggy. Extreme cases is a fully loaded diesel truck with a 15,000 lb 5th wheel camper. She is not stopping as fast as it was unloaded. Or even a truck loaded with 3,000 pounds of gravel in the bed, still takes a mile to stop. This is some of the most illogical facts I have seen in a while.

[@Deweeyy]

We need another jason with a whiteboard for this episode!

[@fourthdalisay2542]

Yeah, I've known this for a while tho never really talk with someone about it, weight only affects the acceleration and cornering speed? And the things that affect your top speed are the power of the car and the air drag. (Created before watching the video & just by reading the title) Edit: I'm intrigued by adding weight does not worsen the braking distance

[@iqtidar91]

wow such an expert

[@younggoat8304]

It does worsen breaking distance because the brake power required to stop a vehicle varies directly with its weight and the “square” of its speed. For example, if weight is doubled, stopping power must be doubled to stop in the same distance.

[@gottliebdee263]

With a runway long enough to reach Vmax yes, but the longer it takes to get to Vmax affects whether you'll actually get there or not.

[@alyousuf]

this is only true if cars produced all their power instantly everywhere and didnt have power curves and gears where power and torque multiplication are not constant. You could effectively make a car so heavy that once you upshift from 3rd at full power to 4th gear, the revs drop to a point where the engine is making %75 of its total power and acceleration (which is effected by weight) will continue to drop infinitesemly closer to zero.

[@ssbeckman]

At 50, in a school zone 😂

[@easy_s3351]

Two types of drag: rolling resistance and air resistance (I'm not a RuPaul fan). Rolling resistance is partly determined by the friction between the tire and the road surface. The friction force Fₓ depends on the friction coefficient μ (on average 0.9 for dry asphalt and 0.4 for wet) and the normal force N, or as an equation Fₓ=μN. The normal force N is determined by weight m (mass) and gravitational acceleration g, or as an equation N=mg. Put the two together and you get Fₓ=μN=μmg, or friction force equals friction coefficient times mass times gravitational acceleration. So N=mg and with g being constant (g≈9.8m/s²) the bigger the weight m, the bigger the normal force N. With the friction coefficient μ also being constant (a cold tire has a constant friction with the road surface, that doesn't change as the speed changes) that means a bigger normal force N gets you a bigger friction force Fₓ. And that means more energy wasted on overcoming that friction force which in turn means less energy available to reach top speed. It is why, for example, a truck can obtain a higher top speed when empty than when fully loaded. Ask any truck driver. There are of course some buts and ifs. You could be fortunate enough to drive on a very very smooth dry road on some very soft rubber in which case the friction coefficient is 0 and there is no friction to influence the rolling resistance. Or your tires could be nicely heated up in which case a difference in speed does mean a difference in friction coefficient because that heat changes the chemistry of the rubber resulting in a lower friction coefficient at higher speeds. And the overall influence of the friction between the tires and the road surface on the top speed isn't that big compared to that of fir instance the air resistance. But in general more weight means more friction with the road, which is why F1 and Indy cars are able to heat their tires up faster when carrying more fuel. Unfortunately, as every F1/Indy driver will acknowledge, that extra weight does slightly reduce their top speed (and make them wear out their tires faster). It's actually quite easy to check out for yourself: go on a push bike ride (preferably on a level road) and see what top speed you can obtain whilst delivering a certain amount of power. Do it again with a heavy backpack and see if you can obtain that same top speed whilst delivering the same power. BTW, weight being a limiting factor in the top speed that can be obtained is what's at the base of Einstein's theory E=mc².

[@masterleon40]

So you just explained why rolling resistance increases. The video explanation already accounts for that.

[@easy_s3351]

@@masterleon40 Ouf, this is over 2 years ago so I had to watch the video again and read what I wrote again. The video states that adding weight doesn't affect top speed and I disagree, as my explanation of rolling resistance shows. Video also states that a heavier vehicle would brake faster, which also isn't true.

[@masterleon40]

@@easy_s3351 disregarding that last part, you don't take into account suspension, which is also explained in the video.

[@easy_s3351]

@@masterleon40 Because that's BS too. The effect of the amount of weight you'd have to add to a car to make it sit low enough to significantly reduce its air resistance far outweighs the reduction in air resistance. Just take two similar cars and add 1500 kg to one of them and see which one has the better top speed.

[@masterleon40]

@@easy_s3351 Wouldn't it depend on the properties of the suspension? At first glance it seems that suspencion has to be pretty hard for it to drop so little to not be enough to compensate for increased rolling resistance once significant weight is added. I reckon most cars have moderetely soft suspensions.

[@loukas371]

Ok I knew this but that last part about the breaking distance, I don't o.O

[@Ludak021]

yea, if there are 5 of us in my Micra, disks overheat the moment I press brakes and I basically loose all braking. How about that?!

[@user-gc1zn5mn4p]

You don't have to watch this video to learn that--the power to weight ratio affects acceleration, not constant speed.

[@oscwede]

can someone explain the braking distances thing? Is it because added weight increases traction, and limiting factor in braking distance is tire traction and not brake power?

[@TexasScout]

No, it just changes the amount of time it takes to get to top speed.

[@2ndProtects1st]

Nice car behind you.

[@abdullahamir351]

"50 at a school zone" 😂😂😂😂

[@tylerdurden4080]

Dodged a bullet on that one, we make homemade ice cream.

[@Ganserndorf9411]

As others have posted, 2x the speed required 8x the power to overcome aero drag.

[@7cougar0]

If it's already posted, why bother?

[@Ganserndorf9411]

@@7cougar0 To support the point...

[@fucatypr]

love the background cars e30 > *

[@bremCZ]

Fully load my car with passengers and luggage and it squats about 5° of negative camber on the rear end. It dramatically reduces the top speed.

[@McBeamer94]

@0:07 ...and finding out that there's also a certain sort of chinese coffee made of cat poo.

[@robsolf]

I do like these vids. Though the big headline of this should be that top speed doesn't matter much in situations that are important. And that if you fill your car with buddies you'll run a far worse lap time than if it was filled with a jockey.

[@segaiuolo]

Filippo Ganna hour record was obtained with a bike weighing 11 kg when the usual weight of a racing bike is about 7

[@captainobvious9188]

I realize this is about acceleration and not too speed, but this is one reason why the R35 GT-R performance breaks expectations when it came out. It has sufficient power that it would be traction limited in most circumstances if it were not for its weight, and by the time its weight would significantly hamper acceleration, aero drag becomes the dominant force to overcome, but it is “light” on drag with an unusually low drag coefficient for the performance class it is in.

[@PiDsPagePrototypes]

1. ARTIFICIAL Vanilla - real Vanilla is a plant extract. 2. Newton's Second Law tells us the mass influences the rate of acceleration. Thermodynamics and Aerodynamics influence the final speed attained.

[@987ntn]

I can't wrap my head around this. So theoretically you could load a car with 10t of weight and it would still reach its top speed (or very close to it, as you said)? Would there be any limit to the weight added, provided the car can still accelerate, no matter how slow? It just seems impossible to me

[@aarinpardhi8560]

I had the same question. But from the video what I understood was that say for example your car has no resistance, so your engines only have to increase the speed of your car not push back against anything. It might help to think of a rocket, the ones with ion propulsion or solar sails on a space ship, no resistance means that the space ship can be pushed over a long period of time through space (where there is almost no resistance)so over a long period of time the speed gradually increases and makes a difference even though on earth these forms of propulsion might not be strong enough to push a toy car because of resistance. Try think of it in the same way. This explanation will either make no or a lot of sense. Sorry if it didn't.

[@ExMachinaEngineering]

No, the video talked about regular loading situations. Typically, those predicted by the manufacturer when creating the different tyre pressure recommendations. So adding a 10t weight to a normal family sedan would play all sorts of havoc with the suspension, engine, and tyres. Not to mention you might kill the engine on the way to its new top speed. Generally speaking, not many things in physics scale linearly.

[@timbrown9731]

However when I try to reach my top speed running that’s a different story 😂