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!

 

[Pawel Ziolkowski]

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.

The point is that all this talk about curing understeer or oversteer through control of weight transfer with dampers, really is in effect for a split second. Or in other words, after weight is transferred we are done and back to whatever balance is dictated by springs/arb/aero etc.

Now the issues of learning simracers usually go beyond such short timespans, if it undesteers it does so all the way to the apex. So instead i think it's more productive to set up dampers to provide most raw grip (in steady state, no transfers) that is rarely mentioned anywhere because it has to be done experimentally for each car on each track and sometimes even for each driver.

In the book mentioned above author goes through steps of tuning dampers, it looks like this:
1) drive couple laps with minimal settings on all dampers
2) increase one setting on all dampers until you feel car is not gaining speed then go back 1-2 clicks
3) continue testing for only two dampers (front or rear) to find optimum grip.
4) repeat for other settings until grip and control is satisfactory

Nothing about weight transfers, and the chart (posted by Richard some posts above) was included as a bonus from other engineer as a blind helper guide for when your car is tuned well and needs extra changes to cope with changing environment (different tyres, driver etc).

You could argue that that's the point of setup in game, and yes it does work that way too, but are you sure the basics are ok? Because often there is bigger elephant in the room than the mouse called "weight transfers".

 

[Tbear]

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

Yeah ... me neither. That school crappola don't work anyoldways.

I found a used 3rd ed. for under $20 ... and ordered it on your recommend. So I'm holding you directly responsible if reading it turns me into an alien! It will fit nicely on the shelf with my dated yet still very good copies of Race Car engineering & Mechanics by Van Valkenburgh and the "... to Win" series by Carroll Smith, among others.

 

[Richard Dastardly]

The point is that all this talk about curing understeer or oversteer through control of weight transfer with dampers, really is in effect for a split second. Or in other words, after weight is transferred we are done and back to whatever balance is dictated by springs/arb/aero etc

And that's also another reason why you shouldn't make detailed setup changes until you're either consistent or know your driving style. Generally once your driving has settled the entire corner entry will become continuous weight transfer as you roll off brakes and shift weight round the traction circle for cornering grip ( and somewhat the same for throttle on exit - late apex generally means that is a bit more abrupt ) - but if you're harsh on the brakes and can't trailbrake then there's no smooth progression there & there's probably periods of time you're not using full traction, no amount of damper work is going to correct that.

. and ordered it on your recommend. So I'm holding you directly responsible if reading it turns me into an alien! It will fit nicely on the shelf with my dated yet still very good copies of Race Car engineering & Mechanics by Van Valkenburgh and the "... to Win" series by Carroll Smith, among others.

I only picked it up recently & haven't dug through all of it, but if you're an engineer, like cars & racecraft I can't see it being particularily disappointing. I need to find a decent & still cheap book on race aero sometime, most of my aero knowledge is about aircraft.

 

[Tbear]

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?

I agree with your assessment considering the AC tuning guides I've seen ... The information in them is correct, but they do NOT give directions clearly. This may be a language/translation problem ... but I don't know for sure.

For example, I think the writers could have been clearer about stating "move toward the smaller numbers increases brake bias to the rear, moving it to the higher numbers moves braking bias to the front ... for simplicity sake AC could have just put a sliding scale/switch marked "front" and "rear", but they didn't do that. Similar with toe and camber.

To answer your question directly, when adjusting toe ... moving the front of the tire in towards the center of the car is positive, negative is when the front of the tire points outward.

You have Negative Camber when the top of the tire is moved to the center of the car, and positive camber when moving the top of the tires away from the center of the car.

 

[Kek700]

Why setups confuse me !

I get tyre pressure and temperature.
I get gearing. Including coast and power.
I get camber up to a point.
Rear wing.
Rear toe
Abs and traction
All these settings i can alter and make some sense of them.

So i picked a circuit i hate ( Donington GP ), i am racing there this weekend anyway.

Set the above gearing,camber, wing, tyre pressures, Coast and power and rear toe.
picking my favorite setup i painfully knocked out some laps
and got a best time.

I then completely reversed eveything ( exciuding the above mentioned settings )
Front Toe,sping rates, damper settings, Anti roll bars and keeping ride height the same both
ends.

Drove the car again and got the same lap times. And much the same feel.

Is it me or am i missing something. ( i usually do )

Can anyone shed some light on this.

 

[Richard Dastardly]

I then completely reversed eveything ( exciuding the above mentioned settings )
Front Toe,sping rates, damper settings, Anti roll bars and keeping ride height the same both
ends.

Drove the car again and got the same lap times. And much the same feel.

Is it me or am i missing something. ( i usually do ).

Yes, that sounds like it was you if you can't feel changes in setup then you're not pushing enough, simply. Or, well, something is wrong in your driving anyway.

Brake bias numbers are simply the % of total brake force in the front wheels, no need to overcomplicate it.

 

[Kek700]

Your probably right.

 

[Pawel Ziolkowski]

@Kek700 Humans learn simple things by repetition but when learning complicated (hard to repeat) things another mechanism can kick in: improvement by similar action.

Each time you changed the setup, you felt improvement, but it was not necessarily because car was better but could be from fresh situation that switched the practice from difficult repetition (slow, not noticeable progres) to relatively easy adaptation (noticeable improvement felt but from less known base), bringing out the best out of your driving.

The way you coped with each setup change was subconsciously stored in he brain (they are not permanent unfortunately).
So when you returned to default setup you were armed with much more tools to work with on laptime.

To make more sense out of the setup you need to give it more time and have more methodical approach so that you know when it's your driving and when it's the setup that does the work. Don't rush toward better laptime, instead make sure the setup change you've found working is actually there by for example taking a break or switching track conditions or just hammering 50laps with it.

 

[Richard Dastardly]

There is also a slight chance that you lucked into an alternative setup - if you had stiff rear ARB & soft springs, and stiff front springs & soft ARB, when you swapped them you might have just ended up with the same cornering balance. You should have noticed some other handing changes though.

 

[Kek700]

I run a gtr gt3, always have, and it a has a reasonably we’ll defined setup, being front engine
rear wheel drive with a 68% brake bias, so that gives a reasoable clue to weight bias.
Once i get to shocks, arb and springs i have never made any tangable progress wih the car
and all the research has never yielded any thing either.

 

[Pawel Ziolkowski]

@Kek700 GTR is one more the more difficult cars to set up. So much stuff is interconnected and full of quirks that are sometimes unsolvable by setup. It's a minefiled. But It's the gtr gt3 i probably know the most about, if you want to know some more about it shoot me a pm or make a new thread for it specifically.

Just for a random example, have you noticed that GTR has negative squat? (rear rises up on throttle and squats down when braking).That is one of the reasons why it snaps on throttle sometimes - rear rises enough to stall the diffuser which is totally not what would you expect

 

[Richard Dastardly]

I should point out there are no front engined GT3 cars; they all have engines between the axles aside from the 911 - irrespective of where it is in the road car - & iirc they're all close to ideal weight distribution. Brake bias isn't an indicator of anything much, there's a reason you can change it in the car.

As Pawel said though, the GT-R is... quirky.

 

[Kek700]

Yes and no, i have noticed it , but i have always assumed it was a rear traction problem and
countered it with diff.

Will start another tread to maybe help others using the Nissan.

 

[Tbear]

Brake bias numbers are simply the % of total brake force in the front wheels, no need to overcomplicate it.

Unfortunately all that the writers (and designers of the AC program) of these AC tuning guides offer is just a percent. They never explain what the =/- is the percentage OF!

As you say ... they MEAN "% of total brake force in the front wheels" but they NEVER explain you are moving towards more in the front or rear. It is impossible to determine what which way they (you) are adding the adjustment from their lack of explanation.

It's easy for old hands to understand what the writers mean ... but I can see how a nube or intermediate is lost by the instructions.

I'd rather be told and know, then assume ... and be wrong.

 

[mclarenf1papa]

Unfortunately all that the writers (and designers of the AC program) of these AC tuning guides offer is just a percent. They never explain what the =/- is the percentage OF!

As you say ... they MEAN "% of total brake force in the front wheels" but they NEVER explain front or rear. It is impossible to determine what which way they (you) are adding the adjustment from their lack of explanation.

I'd rather be told and know then assume ... and be wrong.

For this and most of the other things you mentioned, google can very quickly and easily provide the answer.

 

[Tbear]

For this and most of the other things you mentioned, google can very quickly and easily provide the answer.

But why should I go to google if I am holding an AC tune up guide in my hands?

One or two sentences explains the entire thing with no need to go elsewhere.

As example ... on the Pro tyres app, we get a numbers in four corners that look like this :

-2 +1

-2 -1

OK ... so does the "-" mean that we have too much air, or too little air in the tyres? Should I put in some air, or take some out? ... and just how is the Nube or intermediate driver to understand that? It's not explained clearly in the texts, and as I understand the OP's questions ... this is at the very heart of it.

As it turns out, the above example indicates that we need to put in (i.e., add) 2 pounds in the lefts, Take one out (i.e., subtract) from the right front and put one in (i.e., add) one to the right rear .... which is opposite of what the signs in front of the numbers say. Very confusing for a new boy!

 

[mclarenf1papa]

But why should I go to google if I am holding an AC tune up guide in my hands?

One or two sentences explains the entire thing with no need to go elsewhere.

As example ... on the Pro tyres app, we get a numbers in four corners that look like this :

-2 +1

-2 -1

OK ... so does the "-" mean that we have too much air, or too little air in the tyres? Should I put in some air, or take some out? ... and just how is the Nube or intermediate driver to understand that? It's not explained clearly in the text.

Because you don't know enough to use the guide. It's not the guide/app's job to teach you everything you need to know about car setup - it's a supplementary tool. Expecting it to teach you everything is like buying a car and expecting it to come with a manual that tells you how to drive it. The manual will tell you what the buttons do, sure, but some bits of knowledge are assumed.

Additionally, ProTyres is a very bad example as it has a very comprehensive description of every component of the app on its download page....

 

[Tbear]

Additionally, ProTyres is a very bad example as it has a very comprehensive description of every component of the app on its download page....

BUT it dosen't explain what I just mentioned. It just isn't there.

This is turning into one of those internet arguments.

I say the information isn't clear for nubes and intermediates ... you say its just fine.

No probs... you're right ...

 

[Pawel Ziolkowski]

nubes

What is a "nube" ? Newbie is probably the word to use here.

Also i would agree with you if not for the fact that to get anywhere with setups it requires the ability to explore other resources and learn by yourself, like in college if you can't figure basic stuff out by yourself you drop out.
Yeah better tooltips would be great, but newbies then will be stuck a couple steps later anyways so i don't feel it would change much.

 

[mclarenf1papa]

BUT it dosen't explain what I just mentioned. It just isn't there.

This is turning into one of those internet arguments.

I say the information isn't clear for nubes and intermediates ... you say its just fine.

No probs... you're right ...

That picture alone answers your question. "Target lines range 2psi" and the one on the right is 24 psi, at the bottom target line.