What Sim Racers Don't Understand About Weight Transfer

[@GuagoFruit]

How do I transfer the weight from my belly into the front left tyre going into turn 1 of Barcelona?

[@TeamHorneyRacing]

MOAR snacks

[@catnipherb]

Only Dalking knows, and he's unwilling to share it. Thats why he always wins.

[@Ferrari255GTO]

Yeet yourself out the window in the exact oposite direction the tyre you want the grip on is on relation to you, that way you'll get a slight speed and grip boost. When grip is required on the rear, a cow rigged to fall from the sky on your trunk will give a momentary boost of grip, but make sure your rebound isn't too high or you might loose that grip quickly.

[@kennyk4134]

Very , very carefully.

[@Nick18Racing]

This the man going into turn 1 next to me 😂😭🤚

[@SuperMassiveGrayCat]

You missed one crucial point: under all weight transfers the sum of car weight and downforce doesn't change, so when say left tires increase their grip right tires loose. And there is a crucial point there - due to nonliniarity of actual physics this gain / loss is not equal, you instead loose more (you can describe it as grip coeff being not constant but dependant on normal forse when you come close to grip limits). So you need smooth movements to minimize weight transfer so that cars mass moment doesn't add a lot to the transfer induced by acceleration of the center of mass. Also that's why constructors of sport cars are so obsessed with lowering the center of mass - it reduces weight transfer. And one more thing: on say RWD car you actually don't need 50/50 weight distribution, you are ok when driving wheels carry more than 50% of weight (most mid-engined cars have 55 to 60% of weight on rear wheels). That's why Porsche is actually a successful concept. (And that rear-engined FWD car is not).

[@jn1211]

the "aha" moment when you explained how the traction circle thingie works was absolutely mind blowing lol

[@OverTake_gg]

😂🙏

[@RukaGoldheart]

I must say being very nerdy about cars, racing and of course sim racing as well. The explanations in this video were very nice for people who are just getting into this hobby.

[@gooo1762]

That traction circle changed my life. You literally explained it so fucking good!!

[@jaywung7616]

Just found your channel, that was great stuff! I recall older Forza games depicted a traction circle for each individual tire. It is a great way of showing the effects of weight transfer on over and understeer, as well as dynamic transfers like the Scandi flick

[@Ferrari255GTO]

The live data graphs are still available, it's just that the function isn't mapped to the original controls. Really usefull stuff for tunning if you know what to look for.

[@F.Piccolo]

You're too modest Emily, you're brilliant and fun to watch. I understood most things about weight transfer but you've made me look at it differently and pointed out some areas I've overlooked, which is probably were I'm losing time. I've been trail braking for years, but I feel I probably need to improve that as well, so I'll be looking for your video on the subject. I always enjoy your videos and look forward to seeing more. Cheers Emily! 🍻

[@TheGabe92]

Fully agree. The explanations in this video are more than solid enough to not require a ninety second disclaimer at the beginning of it. Well done and appropriate level of depth for the task at hand!

[@szut88]

I think the concept that is missing here is the slip angle, and an explanation of the relationship between the slip angle, the lateral grip generated by the tyre, and the tyre load. The mixing of these three explains why a four-wheel drift generates more grip than putting all of the load on a single tyre. These are very well explained in a book called "Tune to win", which I happen to known thanks to the Grand prix Legends manual.

[@nicolae-alexandruluca7853]

@@szut88 indeed slip angle is very important, to know where your tires reach their limit before eventually being too much and oversteer or understeer, also steering range is equally important, you can essentially have all the grip in the world if the range of the tires are too small as most civilian owned stock cars are at 25 degrees whereas race cars might push 30 and above and drift cars van have maybe above 40 degrees

[@widelensmtb4952]

Nice one,this should help me visualise what's happening with weight transfer.

[@TeamHorneyRacing]

We asked for it, Overtake and Em delivered. Really useful and fun video. 10/10 MS paint skills yet again. Next I want to see an MS paint backed video on how the irating and SR algorithm in iRacing works. 😂

[@m4rtniw488]

Ready Amazing how you explained that ! Trank you

[@eudesrafael3029]

Fantastic explanation. I'm not mechanical engineer, I'm an electrical one and studying aeronautics but I think your equation explanation was very very good!

[@mauriceroijen7486]

Great video again Ems. Christal clear explanations with good examples. Thank you so much. (Watching your video about trail braking did indeed let me improve my laptimes.)

[@imakestuffhere]

Emily, really good tips and well explained and delivered

[@Ferrari255GTO]

Weight transfer is something that is best to learn early to get the most out of it whie learning everything else around it. A good car to learn this is the Renault Clio Williams Kit Car mod for AC, it's as fun as a FWD car gets (personally i despise most of them) while still requiring precise enough input to learn stuff.

[@davidenativo]

Regarding engine layouts, you missed a fundamental aspect that affects weight transfer too: whether the engine is longitudinally or transversally mounted (something that is modelled only in a handful of sims, like the original Dirt Rally or AMS 1 and 2 and iRacing I believe, maybe Beamng too). The former revolve around the x axis, which means that under acceleration they roll (try blipping the throttle while the car is stationary and in neutral to see it happen) and this makes them less prone to corner but stabler on a straight line. The latter revolve around the Z axis, which means that under acceleration they pitch and so they like direction changes more but are generally unstable. Also, engine layout, longitudinal or transverse, affects wheel base length, which also affects weight transfer, with shorter wheelbases cornering more while longer ones being more stable on a straight line but less prone to cornering. A brief summary? All of the above is why rally cars have almost always transversally mounted engines and short wheelbases, while F1 have almost always had longitudinally mounted engines and a longer wheelbase. The former go way slower and have to negotiate slow corners and hairpins, while the latter go faster and aero works only past 150 kph so fast corners are where their game is at.

[@void_snw]

One thing that'll help understand this: weight and load is good, mass and inertia is bad. We can't move mass around, but we can move what path that mass's weight takes through the suspension.

[@DrR1pper]

The understeer is not what's making the tyre heat up realling quickly. It's just the fact that the tyre is being put into a large slip angle, causing maximum stretching of the tyre wall which is what is generating the heat in the tyre. The understeer is just a by-product of going into a large slip angle without first having built up yaw rate in the car and it's a desirable one here because the driver isn't trying to turn the car when doing this on the straights, he's just trying to get heat into the tyre. There would be just as much heat put into the tyre with such a slip angle IF the car were not understeering and in a turn. It's just that if they only did that to get heat into their tyres on the warm up lap, then they're wouldn't be nearly as much warm up occurring due to the large amounts of straights that would otherwise go unused to warm up the tyres.

[@gooo1762]

Thanks for the video. Really helpful!

[@camraceranimation]

I just wanna say that this channel is dope. That's it. Thank you!

[@OverTake_gg]

Our pleasure! ❤️

[@charliebeckey6269]

Emily is awesome!

[@w201-og]

Great video, thank you very much!

[@F.Piccolo]

I can't seem to connect / find the video you were referring to that you mentioned about trail braking... you pointed to the top corner of the video and the link isn't working for me. 😳

[@racerjason2910]

Well done Emily. Brilliant explanation.

[@sundarworldTV]

Great video but surprised there isn't another 20 minutes detailing why your Porsche is trying to kill you.

[@Vronsky-dd8mg]

Fantastic video! Thank you 🏎🚙

[@OverTake_gg]

Thank you! 👍

[@pasteghost428]

"Friction is gud." Michael Scott - "that's what she said!"

[@MauroDomenici]

The reason why rear engine FWD cars don't exist is exactly for weight transfer. FWD cars have not good traction during acceleration because weight shift toward the back, losing grip on the front wheels. Putting the engine in the rear makes this problem even worse, so every FWD car has front engine to keep the weight on the driving wheels as much as possible (sorry for bad english)

[@ellisjackson3355]

Good info, well explained

[@OverTake_gg]

Glad it was helpful!

[@detourist5541]

Thanks for the great video! - Quick OT question, if I may: You have a Discord link on the Overtake website. It doesn't seem to work. Is the server still active and open?

[@nomaschalupas2453]

The thing is that I have a big ass head…..when the cars weight goes right my head goes left and I could feel it canceling out. Wtf…

[@Pillokun]

The issues with games is that they seem to incorporate a car model that is there only for the animation and eye candy, so far when I play these sims I just get fed up that even my cad software from late 90s early 2000 actually used the models you created as physical models but modern games seems to rely on unseen boxes that simply slides upon the floor(track) so when we look at the suspension/tires it is just eye candy as it is very little to do with the physics so to speak. Would be awesome if a game actually would model a proper car with all the body flex, and fluids and electrical working like irl :P would kill the cpus with 24+ on track but whole moly :D

[@TeamHorneyRacing]

Look up some BeamNG vids on here. That is the physics sim for you. It’s amazing.

[@PingersEst]

Glad to see few rally clips here and there :D To my sadness, You didn't talk much about AWD and rally.

[@Paulo-py4mm]

I get that you're not a mathematician but I feel like you should remove the static friction equation as the description here isn't great (and tbh its not necessary). The circle of grip and dynamic weight transfer explanations are much better.

[@SuperMomToo1965]

just for curiosity, is a square rotated 45 degrees more correct than a circle for rappresenting accurately how much you can steer and break simultaneously? Because I think that those are inversly proportional but I'm not sure

[@vsm1456]

there are many factors that affect grip graph (like aero, corners characteristics, acceleration capability of your car, tyres and suspension, etc) so it can hqve different shapes, but if you get rid of all of that you should get a circle

[@NinetyTres]

More grip, more speed, more fun, got it ;)

[@OscarWildYT]

0:40: “I’m not a physicist or a mathematician or smart at all”. Proceeds to show an equation I have never seen in my fucking life and that I’ll never understand 😂 By the way, as a spanish guy I loved the intro with “El risitas” 😂 May those two legends rest in peace.

[@dadhats]

isn't the idea of 50/50 weight distribution being ideal a myth or just marketing? I forget where I heard this so take with a grain of salt 😅

[@charliebeckey6269]

Yea, it is kinda a myth. The only situation where 50/50 is best is cornering at steady speed on a constant radius (like a skid pad). Since the weight is evenly split you will use all available grip from both axles. In reality on a track steady state is only at the corner apex, there are the transitions during entry and exit. More rear weight bias helps corner entry because the front axle is not as overwhelmed with both braking/turn in forces. Stronger front axle grip means more rotational ability into the corner. Also on exit more weight bias on rear axle is good to be able to apply both forward traction and maintain the lateral grip.

[@jeromehattkronen2305]

Yes, a marketing ploy probably started by Porsche for the introduction of their 924 in 1976 (it had 50/50). Ironically the 55% to 60% on the rear like in their old rear engined porsches is far more like the ideal for agility and overall grip.

[@vrsickkkk]

💯💯

[@superpv]

A woman driver talking about science? OMG, i'm love hahahaha

[@chipchileos1725]

The Bad News- You are naturally born with a sinful nature and have broken at least one of the law (10 commandments) at least once in your life (Example: a lie) (James 2-10 says if you break one of these laws, its the same as breaking them all), so because of this you're on your way to hell already, everyone is (Romans 3-23) The Gospel (Good News): JESUS, Who is GOD in the flesh, came into the world and died for us, to free us from the curse of the law (10 commandments) and ressurected on the third day so that whosoever BELIEVES in HIM will not perish but have everlasting life! GOD said this! GOD cannot lie (Titus 1-2, Hebrews 6-18) we can lie because we are sinners. JESUS saved us already (Colossians 2 13-14) Just BELIEVE and TRUST in HIM! HIM ALONE, anyone who gives you another Gospel, whether an angel or one of us, let him be accursed, like it says in (Galatians 1 6-9) JESUS ALONE! Not religion, Trust in HIM and you will receive the GIFT of THE HOLY SPIRIT. GOD HIMSELF! JESUS said "Repent ye and BELIEVE the GOSPEL" (Mark 1-15). AMEN!AMEN! AMEN!oooooooo¹¹¹¹¹²²²²²³½⅓¼⅕

[@davidbennettracing538]

This is so painful to listen to…