Can anyone explain the setup explanations?!

[ears]

I'm a total beginner with setups really but I am trying to do basic stuff on cars, just to get tyres working well initially.

But the guidance in AC - I can't make sense of it.

Take brake bias for example. The guidance says 'switches brake bias from front to rear'. OK. Well it's currently on 64% or whatever, I can increase it and decrease it. But what's front and what's rear? Is it 64% to the rear? So if I decrease it it'll move to the front? That's what it feels like, but I thought I'd check.

I struggle with their negative camber explanation too. Click plus / minus to increase / decrease negative camber? There are more double negatives in there than my brain can handle. Can anyone explain what happens in layman's terms?

When I click + does the wheel tip towards its outer edge or towards its inner edge?

Thanks!

 

[garyjpaterson]

Take brake bias for example. The guidance says 'switches brake bias from front to rear'. OK. Well it's currently on 64% or whatever, I can increase it and decrease it. But what's front and what's rear? Is it 64% to the rear? So if I decrease it it'll move to the front?

The value is %F, so 100% would be full front, zero rear. Larger number will increase your likelihood of locking fronts, smaller number increases your likelihood of locking the rears.

Ideally you want to find the point where the rears just begin to lock, then move it forward a click or two. Then you know you are getting the most out of both axles, not leaning on the fronts too much which is inefficient use of the brakes/tyres.

That being said, if you are close to the edge, the 'ideal' value will change throughout a stint (fuel), the type of corner (uphill/downhill, straight line or braking with some lateral load etc etc), tyre wear and more.

Really just find that limit and play around, move it forward, see what happens, move it rear (prepare to spin).

I struggle with their negative camber explanation too. Click plus / minus to increase / decrease negative camber? There are more double negatives in there than my brain can handle. Can anyone explain what happens in layman's terms?

When I click + does the wheel tip towards its outer edge or towards its inner edge?

Thanks!

Really if you are that confused, simply look at the wheel and see what is happening (doesn't work on a car with predetermined suspension animations, so most open wheelers are out).

Works with toe as well.

 

[Tberg]

My approach to brakebias is different, I use it only to control my corner entry and trail braking. Even if that means more or less bias to the front than just locking the rears + a few clicks.

 

[ears]

The value is %F, so 100% would be full front, zero rear. Larger number will increase your likelihood of locking fronts, smaller number increases your likelihood of locking the rears.

Ideally you want to find the point where the rears just begin to lock, then move it forward a click or two. Then you know you are getting the most out of both axles, not leaning on the fronts too much which is inefficient use of the brakes/tyres.

That being said, if you are close to the edge, the 'ideal' value will change throughout a stint (fuel), the type of corner (uphill/downhill, straight line or braking with some lateral load etc etc), tyre wear and more.

Really just find that limit and play around, move it forward, see what happens, move it rear (prepare to spin).


Really if you are that confused, simply look at the wheel and see what is happening (doesn't work on a car with predetermined suspension animations, so most open wheelers are out).

Works with toe as well.

Brilliant! Thanks! Will check next time I'm on but not entirely sure I get that view in VR. I think I'm always in the car. But that GIF helps a lot. Thanks.

 

[garyjpaterson]

Yeah when I say move it back till the rears begin to lock, I mean that as a starting point only - as you say it has a big impact on corner entry depending on the type of corner.

Often Kunos cars have it really really far forward which isn't a nice starting point IMO. At that point you can move it forward/back a couple of % and it will make almost no difference as the fronts will lock regardless.

Thats why I always start with finding the 'edge' and go from there.

 

[Ben Lee]

There is still loads I don't understand about car setup. Dampers for example. I think I understand the principle, however still don't really understand how they work in reality. So like the spring is potential energy, but the damper controls it. So the damper controls the speed at which the force is applied, or something like that. Again, toe, I understand the principle, but don't get how it affects car handling, since I can change it and feel nothing.

 

[Kek700]

I'm not sure there is an exact answer to any setup up, it is more a case of the driver "feeling"
the effects and then using this to alter them via the aero and mechanical adjustments.

( there is a very limited amount of adjustments but they combine when combined to
a racing circuit and driver into a complex problem )

So I am not sure that having an absolute understanding is of any ultimate help really.

"You just need to feel and have a moderate understanding of weight transfer"

Example:-
if at the apex you apply full throttle but have to back out of the acceleration due to
the weight transfer pulling the wieght off the front loaded wheel and causing excessive understeer.

"you could increase the front rebound and rear bound "

Using this adjustment in an attempt to slow the process down sufficiently to keep the weight on
the front loaded wheel in an attempt to stop it understeering and allowing more acceleration
without as much understeer.

But this alteration may adversely effect the car for the rest of the circuit or it may be that this just
does not have sufficient effect.

" So having a feel for the car is again the real answer to making a setup work for you "

Once again I must emphasis that feeling the car gives you a reference to each aero or
mechanical input so you really do not need a in encyclopedic knowledge of each input.

Only my opinion, I am sure most would disagree with all of this.

I have ignored data logging

 

[Richard Dastardly]

There is still loads I don't understand about car setup. Dampers for example. I think I understand the principle, however still don't really understand how they work in reality. So like the spring is potential energy, but the damper controls it. So the damper controls the speed at which the force is applied, or something like that. Again, toe, I understand the principle, but don't get how it affects car handling, since I can change it and feel nothing.

Dampers provide an opposing force to the spring, proportional to the spring movement rate. You can look up the basics of spring damping in any school physics book, the principle is the same.

Putting that in context, your car springs expand & contract from two inputs:
* Bumps/kerbs in the road, which on a racecar you control with the fast damping
* Weight transfer when cornering or changing speed, which is what the slow dampers are for.

You have to picture what happens when the car starts rolling as you start turning - outside wheels have more grip as more weight is transferred, the dampers are controlling the rate at which that transfers. Once you're actually settled in a corner then it's down to the ARBs or springs ( or diff ), it's when the attitude of the car changes, so when the springs compress or extend, that the dampers get involved.

It gets a bit more complicated when you're turning and braking/accelerating, unfortunately, you start having to think about diagonals.

 

[Pawel Ziolkowski]

Example:-
if at the apex you apply full throttle but have to back out of the acceleration due to
the weight transfer pulling the wieght off the front loaded wheel and causing excessive understeer.

"you could increase the front rebound and rear bound "

Using this adjustment in an attempt to slow the process down sufficiently to keep the weight on
the front loaded wheel in an attempt to stop it understeering and allowing more acceleration
without as much understeer.
Sorry but Increasing front rebound counteracts the effect of increasing rear bound, but don't feel bad about noticing it, the actual effect creates like 0.2s worth of balance change.

But this alteration may adversely effect the car for the rest of the circuit or it may be that this just
does not have sufficient effect.

Sorry but Increasing front rebound counteracts the effect of increasing rear bound (so to have any change you'd have to increase one and decrease the other).
But you are right that the effect of dampers on weight transfer is often not sufficient (especially in sims) as it takes like 0.2s to complete, so to really use it you'd have to have a car and driver that can actually do useful stuff (settle in new position) in this short time.

 

[Dan Costa]

There is still loads I don't understand about car setup. Dampers for example. I think I understand the principle, however still don't really understand how they work in reality. So like the spring is potential energy, but the damper controls it. So the damper controls the speed at which the force is applied, or something like that. Again, toe, I understand the principle, but don't get how it affects car handling, since I can change it and feel nothing.

read this!

https://pt.scribd.com/document/381200294/2AdvancedSetupGuideV1

 

[Richard Dastardly]

From "Competition Car Suspension" by Allan Staniforth, which is interesting if you're an engineer but a bit excessive for most people.

 

[Andy-R]

I had a quick read through but didn't see mention of the live values on the right. To the OP, click camber and look at the right side live values and you will see what the change did. Off the top of my head I think it is pretty much always click left for more negative/less positive and click right for less negative or more positive.

 

[ears]

Thanks everyone - this is all very useful and interesting.

I think I need to tighten up my concept of understeer / oversteer a bit too. Like the basics - is the car understeering or oversteering, or am I just driving it into the corner too fast.

Because I guess any car will understeer and oversteer regardless of setup if it's being driven by an impatient buffoon.

 

[Dan Costa]

From "Competition Car Suspension" by Allan Staniforth, which is interesting if you're an engineer but a bit excessive for most people.

Well how about that. My new wall poster next to the computer.

Edit: it seems from a book. Can I know which one? do you have it?

 

[Richard Dastardly]

Thanks everyone - this is all very useful and interesting.

I think I need to tighten up my concept of understeer / oversteer a bit too. Like the basics - is the car understeering or oversteering, or am I just driving it into the corner too fast.

Because I guess any car will understeer and oversteer regardless of setup if it's being driven by an impatient buffoon.

There's a generic term of "overdriving" which covers all that, and yes before you start messing with setup in detail you need to be consistent, or you won't recognise what your changes did. Tyre pressure and probably camber if the car is not set up right by default are something you need to set irrespective of your driving though. There are AC tools to help you with both.

Edit: it seems from a book. Can I know which one? do you have it?

It's in the original post it's published by Haynes, I found a tatty old copy.

 

[Kek700]

Sorry but Increasing front rebound counteracts the effect of increasing rear bound (so to have any change you'd have to increase one and decrease the other).
But you are right that the effect of dampers on weight transfer is often not sufficient (especially in sims) as it takes like 0.2s to complete, so to really use it you'd have to have a car and driver that can actually do useful stuff (settle in new position) in this short time.

Your quite correct, i should have read my post before posting it many apologies.

 

[Andy-R]

Thanks everyone - this is all very useful and interesting.

I think I need to tighten up my concept of understeer / oversteer a bit too. Like the basics - is the car understeering or oversteering, or am I just driving it into the corner too fast.

Because I guess any car will understeer and oversteer regardless of setup if it's being driven by an impatient buffoon.

https://jalopnik.com/the-idiots-guide-to-oversteer-vs-understeer-and-how-to-1795389460

 

[Kek700]

But you are right that the effect of dampers on weight transfer is often not sufficient (especially in sims) as it takes like 0.2s to complete, so to really use it you'd have to have a car and driver that can actually do useful stuff (settle in new position) in this short time.

One other point i forgot to mention

I don’t understand the long time constraint of 0.2 seconds.
Can you explain, simply as possible, the whole process of
setups for me is one of confusion.

 

[Tbear]

From "Competition Car Suspension" by Allan Staniforth, which is interesting if you're an engineer but a bit excessive for most people.

@Richard Dastardly, could I ask which edition of this book do you have? I can find some of the first 3 editions, used but reasonably priced ($20-50) ... but new 4th editions can go for upwards of $633! I'd like to have it, and admit to being somewhat of an engineer, but NOT the $633 type ... not since I stopped going to school anyoldways.

Thanks.

 

[Richard Dastardly]

@Richard Dastardly, could I ask which edition of this book do you have? I can find some of the first 3 editions, used but reasonably priced ($20-50) ... but new 4th editions can go for upwards of $633! I'd like to have it, and admit to being somewhat of an engineer, but NOT the $633 type ... not since I stopped going to school anyoldways.

Thanks.

Third edition. No idea what the differences are between 'em other than I notice some discussion about active suspension. And yeah the current edition is going for £75 or so

I also went to school for engineering, but never used it