Default vs Hack setup - whats the hack? Exos 125 S1

Car: Exos 125 S1. Track: Silverstone.

On the left is the default setup, on the right is a setup which, when i use it, is an instant immediate 3-3.5s per lap quickly. I simply downloaded it off setupmarket.
The thing is, i have no idea why. I just drive and i'm competent enough to drive to a given setup's limits, give or take. So what is going on here? I'm desperately trying to learn how to make setups for any car, I understand the basics - the fundamentals, to interpret what the car is doing and make small changes, step by step, do enough laps to get an average, bla bla bla.....I get all that.

But look at the two setups below, and there are some odd things. The default setup is massively understeery - so you'd think "ok, increase front wing, or, lower rear wing". But no, the hack setup runs 21/30.
I would never think to myself that would be a solution.

But ok, fine, so clearly whoever made it has focused on mechanical grip and maybe made the rear really stiff, and then balanced that out with the aero.....and to some degree he has - ARB Rear on 4, vs 1 on the default.

BUT HERE is the interesting bit - he's slammed the front of the car down to 1, the lowest possible number. Again, i'd never think to do this. He's lowered the rear from 40 to 20, but taken the front down from 24 default to 1!
Why. How. What would make someone do this? and how did he know this would work so well? Has he literally tried every single possible combination to get to this? Of course no - that would take literally years.
So whats the secret there? Maybe he has checked the ride heights and knows when the car is producing X downforce at Y height - but how to check this??

Again with the Packers, he's maxed them out - again unusual.

Anyway, you get my point. However this setup works - it works - it gives a massive laptime benefit instantly, but i don't really know why. All i know is in the effect - the car has virtually no understeer - it is very neutral to oversteer in the very fast corners at Silverstone, yet it turns in brilliantly in the slow corners and is very stable.

Its the ride heights i'm most curious about. Can anyone work out this mystery please? (ignore the tyre compound i know the default is on Soft and hack setup on Super soft, my comparison was with default on SS also)








DEFAULT SETUP CAR STATUS


HACK SETUP CAR STATUS

 

For a starter enable dev apps via assetto_corsa.ini. look at the wings app for aero, suspension app for travel & bumpstop info & car info (i think) for damper ratios & suspension frequencies

 

A couple of quick observations... One of the biggest change is tyre pressure. The default is too high. This "hack" setup is stiffer hence why its nice in the high speed corners. The stiffer & lower rear end which is probably riding the bump-stops more aggressively is countered by a fairly large increase in rear camber, toe in & also diffuser downforce. There is also a considerable increase in rear rebound dampening giving the car more rotation. The lap time decrease is simply due to a more efficient setup. This car has allot of grip & down-force. Everyone has there there own wants, needs & theories when coming to setups. My own personal preference is to never dl other peoples setups. It just doesn't work for me & i would spend allot of time going in circles. Each to there own though..

I also would get too hung up on the slider values within the setup screen. In AC Front=1 can be stiffer than Rear=5..

You can also enable data collection within assetto_corsa.ini & use free tools such as race studio 2 to better see whats going on

[TELEMETRY]
EXPORT_ENTIRE_SESSION=1
DEBUG_PHYSICS=1
DEBUG_AI=0

 

*car engineer app

 

As Coanda says tyre pressure change between setups will be a huge difference, this will be track and weather dependant more then any other setting. Also the setup you downloaded is using softer tyres. I also avoid downloading others setups and just work on my own from scratch, if Ive driven the car at other tracks then I will load one from a similar style circuit to be my new base.

Aero is a big compromise and in these cars you can normally go a couple different ways low/mid or mid/high for similar net results. Front Aero in particular I will go as high as I can and balance this out with the rear aero. Rear wing is the draggiest aero option you have so you want to adjust this for more straight line speed but then need to balance this out with front wing and suspension options to give the balance intended in mid to high speed corners. Do you want more mid corner speed? raise the aero, do you want more straight line speed lower the aero. But if you go too low aero wise and there are high speed corners onto longer straights then lack of exit speed may mean a lower aero setting gets a lower top speed anyway for a net slower lap time so you may still want mid to high aero on tracks that you may think minimal aero is best.

You can also make aero balance opposite to mechanical balance to be able to make a looser aero car on entry get balanced out a little with a bit of mechanical push, then there are slow corners vs mid to high speed. Aero grip wont do much in the low speed turns so you need to set balance mechanically for these and also make it work at speed once the aero kicks in. Lower aero will also increase brake distances and the more aero you run the stiffer you want the car to handle the extra loads at speed. Gearing wise its very much track dependant along with needing to work with your aero setup, learning the basics of setup and how to make changes to help make the car do what you want is a great skill to have. Simply downloading a setup and comparing to the default wont tell you too much as all changes you make pretty much effect everything else so you cant really find one thing that has changed and will make things instantly better on the default.

 

Each car has it's own tricks, the Exos the lower you run the front the more efficient the FW gets so although he is using "only" 21 FW the downforce the car is producing is significant (you can see this through the wings app), running maximum RW makes sense because the drag penalty is rather small.
On the rear the diffuser stalls if the height gets too low so you have be careful.

Other than that it's about keeping the tires in the ideal range, good gear ratios and balancing the car mechanically.

Keep in mind that formula cars are more sensitive than most(all?) other types so the gains that can be made are relatively large.

 

firstly i already talked about the tyres:

the rest of your post has nothing to do with my actual post, i'm sorry. but thanks for the general tips anyway.

 

this is great, i'll start understanding using this.

yeh i'm not reading anything into the numbers, this is all about relative and how 1 setup is comparing to the other. I know i said 'only 21' but thats in relation to this, regarding the wings all i said was

thats interesting, i never thought to think of it in terms of drag penalty rather than increased downforce.
some good clues so far, thanks guys. I'll run the app and look at the data to see whats going on.

 

Another consideration for car setups is rake angle. This will alter the AOA (angle of attack) on the rear wing.

 

The change in gears on the "hack" (I don't know why you'd call it a hack? It's just another setup) are going to make the car way faster everywhere too. That's one of the easiest changes to make any car seem faster.

 

yes, i know. I get it. thats not what i'm on about.
i ignored this in my post because its obvious and that does not explain the massive cornering speed differences, obviously just in some acceleration and top speed/making full use of the revs.

its called a 'hack' in a semi joking way because yes its just another setup - but as i explain in my original post, there are some interesting things going on in it which, if you logically went through testing steps, you wouldn't think to do e.g. the wings example i gave.

Coanda's posts give good insight into it so far.

appreciate the input but i'm not after generic obvious setup advise - gearing is not the reason why the setup on the right is 3 seconds quicker and why the car is so much quicker in corners.

 

That's fair enough but I'd say the majority of that time gained came from the gear and tyre pressure changes. The car was faster and had better grip, that could easily knock 2-3 seconds off the time meaning all the aero changes are minor.

 

you'd bet your life on that statement would you?

 

out of the 3.5s, likely :

1.2 is tyre pressure
1.5 is ride height (may or may not include ride height management through wheelrate and packers)
0.8 is the rest

 

Reduced more front height increase the overall downforce package
Reduce height reduce drag & increase downforce with diffuser

Lowering the front technically make the front spring rate more soft due to the change of center of gravity(mass) which shifted more toward & added bump stop make sense(spring rate have been increase for both front & rear about a similar rate).

ARB rear increase is for the cambered corners & compensate for the rear lower bump damper. The high rebound in the rear is to compensate for the center of gravity that have shifted more toward allow more suspension movement.

Personally I would add a bit more negative camber to the left front due to the lower bump left front.

It's a placebo effect & I could be wrong.

 

Oh no hear we go again... This is sure to open up an old can of worms. This should be interesting. I'm out

https://www.assettocorsa.net/forum/index.php?threads/about-dampers-in-bump-vs-rebound.46777/

 

Formula 1 car, you can do that on this car because aero setups, with wings and ride height, change a lot the car.

The same is not aplied to other cars, that only tyre pressure can make a large difference.

 

@Trezoitao38
Sadly setup make quite a difference in a lot of cars in AC. It's a placebo effect.

 

a softer tyre compound, anyone?

 

how do i know if the car is bottoming out or not, if i lower the car to improve downforce?
is there an app or something i can use to see?