Driving style and setup threads

BhZ · Jan 16, 2018

BhZ · Jan 16, 2018

Here you can find some usefull videos about some of the topics discussed in the threads above (WIP)

Traction circle:

Skip Barber going faster:

AndrewBo · Jan 16, 2018

Sticked...

Ken Bell · Feb 2, 2018

Excellent stuff Matteo

bsmooth · Feb 2, 2018

The book is a good read thats for sure. Didn't see the video before.

BhZ · Mar 12, 2018

@artesina here you can find everything you need. To better understand trailbraking, watch the video about traction circle. If you have any question, just ask here or send me a PM and we'll work on your driving style.

artesina · Mar 14, 2018

BhZ said:
@artesina here you can find everything you need. To better understand trailbraking, watch the video about traction circle. If you have any question, just ask here or send me a PM and we'll work on your driving style.

The video is excellent but my english ...no!

the second video doesn't work
this explain how the possibility work on the tyres and gas/brake/turn mix but not how to see with forcefeedback or other in the game , where is the grip car situation and so how you can use 70 percent of brake and only a bit the weel controll (for example)
difficult to tranlslate what I mean
thx

InsaneOzzie · Mar 15, 2018

Couldn't agree more Matteo

Scott Mansell (No relation to Nigel) from driver61 has a string of great video tutorials on racecraft etc, I recently signed up, it's free, I'm getting all the tutorials emailed to me one at a time and in numerical order. The video's are worth it in my mind as Scott Mansell is a well respected driving instructor, the video's have definitely helped my understand how to get more from myself and the car & track, check it out, you won't regret it and if it's not what your looking for, or of some help to you, I'll be very surprised.

Leonardo Ratafiá · Apr 5, 2018

I've found these channels and seem to be interesting, hope you like them
https://www.youtube.com/user/ChassisSim/videos

Tennisbiki · May 20, 2022

How to tame a snappy rear/mid engine car, like Lancia Stratos?

I hope this is the correct thread to post this. I am sharing my thoughts/experience here, hope others can shine in as well.

There are two Lancia Stratos mod out there, I could find, both of them unforgiving. There is one dated 2015, and the other one is from AC Cars Reworked Version 3.0 released 2020 July. The 2015 car has limited setup options, but the ACCR version has a full setup options for experiment.

The behaviors of these cars is that the car can turn in, and the rear would go into an unrecoverable slide, "typical oversteering" right? The exit oversteering can also be invoked by heavy throttle application. Under the "hood", I found that the mod came with heavy rear arb and less front arb, and the spring weight(wheel rate) is about proportional to the mass bias of the car.

My goal is to make the car more drivable, or forgiving. I want to be able to enjoy the car more, than simply getting a giggle spinning out the iconic Stratos and claim that I know and experienced Stratos. I want to be able to complete a clean lap around Nordschleife or go on Tsubuka Fruitline touge. And I found that I could and have done the Fruitline multiple times.

The biggest surprise or lesson I learned about taming snappy cars is that fixing the other end of the "problem". By dropping the grip on the front, shifting the balance, the rear can break away more gradually.

First step is remove the rear arb. Removing or lowering the rear arb reduce the weight shift to the front which means reducing the rear grip. IRL I drive an 86 MR2. The evolution of AW11 is that first they came with rear arb in 1985 and then did a running change and when the stock went out, the 86 no longer come with r arb. I ran 89 in ES AutoX with a big ST front arb and no rear arb. So adding r arb does not improve the handling of AW11.

Next the front arb is increased, like on my 89 AW11. Again strong f arb shift/weight transfer more load to rear tire, or reduce front grip. But it also make the front negative camber works better so it actually increase the steering feel, oddly, yeah, increasing front grip as well.

The rest is more minor. According to what I read from someone racing TRD and some setup on old Porsche, allowing the front to dive is a good thing to reduce entry understeer. So reduce front bump damping and increase rebound damping to keep the front down. And reduce rear rebound to allow the rear to rebound and keep traction in braking situation.

So what I did was, raise the front ride height just a bit, about 10 mm above the rear, reduce r rebound. I raise the rear negative camber to about -2 deg, front about -0.5. neutral f toe, a hair of rear toe-in.

What I now have is a Stratos that I can enjoy and have fun on Tsubuka fruitline without crashing it constantly. The steering has good feel and feedback, the car is responsive to trail braking/weight transfer. Entering way too high, the front would give skid, adding or easing up on the brake would make the car rotate more, or quicker. The car might still going into a spin if braking during turn, like a downhill entry, but the front is sliding with the rear, rubbing off the momentum. At the limit, there is a little more rear slip than the front, but gradual enough that adding throttle can keep the tail from coming completely around. Overall the car is close to being balanced, and enabling me to "play" and explore the car and the touge. Let me know how this works on other cars.

Background: ME, AutoX, search word "Mr. Lee MR2" (First hit on the net)

stigs2cousin · Oct 17, 2022

How do you determine the amount of camber/toe?

The temp distribution in the AC data doesn't seem to reflect what's going in the tyre patch??

Deleted member 1066209 · Oct 17, 2022

stigs2cousin said:
How do you determine the amount of camber/toe?

The temp distribution in the AC data doesn't seem to reflect what's going in the tyre patch??

I'd like to know too. I'm currently using the "trial and error" method; I make changes in single increments and test them. It's very tedious, but I've learned that a single point can make a noticeable difference.

Tennisbiki · Oct 18, 2022

stigs2cousin said:
How do you determine the amount of camber/toe?
The temp distribution in the AC data doesn't seem to reflect what's going in the tyre patch??

Assuming your question is for me, though I have to confess that I still consider myself a newbie when it comes to setup, since the driving part is also a work in progress.

For MR2 Mk1, there were information available, from TRD and forum, for the alignment setting. Since I was in stock class which means only alignment, front AWB, shocks can be adjusted, the standard method is max out the caster, max out the negative camber, and starting with zero toe. So I guess I always start with a zero toe on all 4 corners and start the testing that way.

It is a bit unexpected that in AC, I actually backed out the negative camber from say -2.5 to about -1~2. Seems yes, there is more grip at more negative camber, but the car is more snappy. But the forgivingness enable me to reach the limit more consistently, rather than crossing the line, the car snappy out of control. Again I am actually quicker with less negative camber in the MR2.
Oh, one more thing, I like lower ride frequency.. Right I prefer low power and low downforce cars. It just feel better for me.

stigs2cousin · Oct 18, 2022

Thanks Tennisbiki

Problem is that what I (believe to) know irl doesn't translate into AC.

I don't know the tyre data, I don't know how acurate AC models the camber and toe curves and especially how well the tyre temps mirror the working of the tyre patch to the tarmac.

And worst of all I can't inspect the tyres for camber/toe wear which tells a lot after some test driving.

One could probably "drive it out", means collect the data empirically but I lack time, motivation and some driving consistency to make it worth wile

MFG Carsten

Tennisbiki · Oct 18, 2022

stigs2cousin said:
One could probably "drive it out", means collect the data empirically but I lack time, motivation and some driving consistency to make it worth wile

Yes, I hear you. I agree and I am kind of in the same boat.
When I started out, I used some of the apps, such as suspension to see the changes of camber n toes while the car goes in and out of cornering. It was interesting to see some of the mod cars have the camber went into positive as they went into a spin. So I learned to play with the suspension pickup points to change the camber curves. And it helped. Some of the things such as lowering the car too much need to roll center adjuster to move the outboard ball joint down actually works.
But ultimately it is how the setup works with the driver. So taking a car you connect with and a track you can drive consistently and just invest in some time. At a certain point, you introduce one variable and see how it works. Yeah, it's mind boggling what one can do to mess up the setup. Plus some time you work the opposite end to fix the problem end.
Whatever you do, try to have fun. I have to remind myself of that.

Tennisbiki · Nov 2, 2022

A little update on my journey to learn about car tuning..

So lately I have been keeping the Car Engineer on while trying out different cars. I noticed that the ride frequency and the damping are all over the place. While before I was aiming for about 1.5~1.8 Hz for my MR2 Mk1 with damping, based off the spreadsheet with rebound ratio about 1. I thought that was very good. But then I drove a beautiful Europa mod, with ride frequency about 1.1 Hz and rebound about 1.5. That car drove very nice. I thought that the Europa was very stable and composed. Where my MR2 is a bit .. loose, like too much motion.

Then there is the Suzuki Altos with ride frequency about 3.1 Hz and damping about 0.3. No wonder this car is so nervous. The Caterham has ride frequency 1.4/2.1 Hz and rebound about 1/0.8. I thought the Caterham drove nervous. and want to lower the rear stiffness to even or lower than the front. The beloved M3 is at 1.3/1.5 Hz and 0.9/7, about the sweet spot. Another beloved AE86 is at 1.5/1.7 Hz and rebound 1.0/0.82. I thought the rear end bounces around too much perhaps lowering the rear wheelrate closer to 1.5 Hz can help. Another well regarded car, NA Miata is at 1.4Hz and 1.5 rebound. Hmm.. I thought it drove kind of dull but .. that car is growing on me.

Race car in general has higher ride frequency of course, with the high downforce car even higher. But I am seeing ride frequency near 2.0 Hz even for street cars, that is silly. With high frequency there is very little suspension travel and chassis roll. I suspect that for someone who does not want to deal with suspension geometry, slapping a stiff suspension will cure most handling evil. For pure speed perhaps high ride frequency works but for my enjoyment .. it is like premature orgasm.

So lower ride frequency means the chassis moves more, I also notice that the car respond a bit slower, well because it takes time to get to the longer travel range. I personally like having a bit more time, a bit more feel, or room to fudge. And damping can make the chassis movement less violent. Though too much damping dulls the car, and too little make the car too lively. One might need more damping for quick transitions.

Just my 2 cents.

Deleted member 1066209 · Nov 2, 2022

Thanks for sharing your observations. What is "Car Engineer", and how do you enable it? And how are you measuring your ride and damping frequencies? Do you watch the values while you're going down a straight, like at Monza? I suppose the bumpiness of the track would play a role in obtaining proper measurements.

Tennisbiki · Nov 2, 2022

justwannadl said:
What is "Car Engineer", and how do you enable it?

I think it is called AC car engineer. If you have Content Manager ->Setting->Assetto Corsa -> APP Windows. I have the Developer apps selected. and it is the first app on top, on mind.

While in Drive mode, hover the mouse cursor to the right edge of the screen to select the apps.

Car engineer shows Car mass, unsprung/sprung mass, ride frequency f/r, and bound and rebound ration f/r. Those values are static because they are the basic parameters of the vehicle selected. They will not change while driving. I just found them useful to know when I adjusted the wheelrate and damping rate. Goog luck!

Deleted member 1066209 · Nov 3, 2022

Thank you so much, I didn't know such a wonderful thing existed. Your advice is greatly appreciated!

RasmusP · Nov 3, 2022

stigs2cousin said:
Thanks Tennisbiki

Problem is that what I (believe to) know irl doesn't translate into AC.

I don't know the tyre data, I don't know how acurate AC models the camber and toe curves and especially how well the tyre temps mirror the working of the tyre patch to the tarmac.

And worst of all I can't inspect the tyres for camber/toe wear which tells a lot after some test driving.

One could probably "drive it out", means collect the data empirically but I lack time, motivation and some driving consistency to make it worth wile

MFG Carsten

AC lacks quite a bit of fidelity when it comes to tyre temperatures, camber, toe, wear etc.
If drives very well and behaves realistically enough for most, like positive rear toe tames the rear, while negative rear toe gets you sideways more easily.

But toe barely influences tyre wear or temps at all.
Camber is similar. It's more about the grip balance, than about wear/temps!

To find the perfect camber, there's only one way for AC:

Camber Extravaganza

Camber Extravaganza App for Assetto Corsa to show wheel camber angles in real time, helpful for tuning suspension. Shows instantaneous and peak camber, and has an optional short-term history graph with some settings to play with. Calculates...

www.racedepartment.com

Put that into your vision while driving and then adjust it until it's barely going red during the important corners.
You can balance things a bit by lowering the front camber a little while raising the rear camber to not get snap oversteer on exit kerbs.

Or you can make a car turn nicely and accelerate very well out of corners (without kerbs) by raising the camber to never go red but let the rear tyres go slightly red at the exit.
This makes the rears having less lateral grip, but more longitudinal grip. The mx-5 cup is a car with such a setup at default.

On tracks where you need the maximum acceleration it's usually faster to trailbrake until the apex and then go into a slight drift with red-camber rear tyres.
Giving you higher acceleration while taking a tighter line.

On tracks with longer corners, where it's all about keeping the momentum with the little mx-5 cup, getting the camber to optimum lateral grip, using all the kerbs and adjusting the balance with the other settings will be faster.

About car engineer app, suspension and dampers:
In theory a softer suspension is better, but if it's too soft, you won't be able to control the car anymore through chicanes or when needing to correct it quickly.
With aero parts, you need a stiffer suspension to keep the aero working like it should.

The dampers can often be adjusted by feel. If the car is too bouncy, stiffen them.
If the car feels like a brick, soften them.
You can then tune the car for momentarily scenarios by mixing bump & rebound settings.
To stop the overall bouncing, the mix of them is important.
But if the front seems to not absorb bumps well enough or you want more grip while turning in under braking, making the front bump softer will let the front dive down a bit more.

The "fast" dampers are still a misery to me though..