HELP: Audi TT Cup understeer

[RasmusP]

Hi,
as you all can see we had some good discussions going on in the last days and the consensus was something like "Let's have a place to talk about the driving".

So here I am, creating the first of that threads:
I need some advice on fighting the understeer in the Audi TT cup
When I watch the replays I see that "the fast guys" are having a better line and when I compare it to me in detail I see they are faster while cornering, turning in point + braking is almost the same and I see no clear difference.
It's like some "magic" that pushes them tighter around.
But then sometimes I get that too... Just don't know how to do it consistently

My thoughts: when you brake you will gain grip on the front wheels. So touching the brakes slightly while cornering will give you a tighter turning radius but will also slow you down. If you brake too hard you will transfer too much weight to the front and you will get understeer.
If you accelerate you will get understeer because the front wheels lose weight and therefore grip.
If you accelerate too much you will get HEAVY understeer, because FWD...

So somewhere in between there seems to be a "trick" that lets you do the "tighter turning radius" you get when touching the brakes, but without braking and without slowing down.

Can you help out? Do I have to turn the wheel more aggressively or trail brake deeper into the corner? I don't know and before I'm spending a few hours on doing a splitscreen slow motion video, studying the details etc. (maybe I will do that either way) I just thought about asking you all and start a nice discussion about the handling of our beloved (and sometimes hated) friendly event car

 

[Mr Deap]

If you can share a replay file of your run or share a video, I can pin point the issue.

 

[StefanoCasillo]

moving weight forward while braking will give you more grip thus oversteer as long you don't put too much stress on the fronts because of the braking itself. Brake bias is the key here to get a good turn in.. the cars can get a bit more front bias than the default, we had to move the default forward because the AI was struggling majorly with the TTs.

 

[Mr Deap]

@kunos Nice tips. I never thought about it..

So more rear bias during braking depending of the setup & how tyre react. I would fail that answer.

 

[RasmusP]

Wow that were some fast answers! Thanks Stefano!
I will try to get a video done

 

[Rupe Wilson]

In the club event in question we do have a fixed default set up, with only tire pressure and tire choice being adjustable.
but it was pointed out on Wednesday that even though brake bias is not adjustable in the set up options it can still be adjusted whilst out on track if buttons are added to the config on the wheel
so i will unlock in the set up options in the next event as it can be circumnavigated

 

[RasmusP]

Not at home at the moment to try it. But in theory:
Moving the brake bias to the rear should "unstress" the fronts a bit when braking right? But the weight shift would be similar?
So in the end you need some kind of oversteer-causing-weight-shift that doesn't stress the fronts?

 

[Rami]

In short, I'd say trailbraking is the "magic" you described there...

 

[StefanoCasillo]

Not at home at the moment to try it. But in theory:
Moving the brake bias to the rear should "unstress" the fronts a bit when braking right? But the weight shift would be similar?
So in the end you need some kind of oversteer-causing-weight-shift that doesn't stress the fronts?

they will still be stressed because they are stil braking but the point is to have the rear with a similar stress so at the end the axle with more weight will "win".
With a lot of front bias the fronts get load but they are also busy braking and the rear is more light but it is also braking less.. thus they end up with more lateral grip and you will understeer. Bias is useful to correct this.

 

[Kek700]

If you would not mind my input, especially as not actually that quick.

I virtually get no understeer with the audi tt ( remember fixed setup ), i am constantly on the brakes and
throttle together in all but the fastest corners.

 

[RasmusP]

- missclicked, will edit later -

 

[BhZ]

@RasmusP since the setup is fixed, there are 2 things you can do. As others have said, moving the brake biad to the rear will help. Also, a more advanced technique can help you there: trailbraking. So while turning in, apply a bit of brake. Too much will give you understeer, but the right amount should give more grip to the front. If you still have the replay of the tt at le mans, you can check my replay to see what i mean.

 

[RasmusP]

I spend the last 2 hours searching for the perfect example and creating a video that really shows what I am asking about.

Here is the link: VIDEO

I did a side by side comparison which let my jaw drop...

I won't write my full analysis of it down for now but the little texts in the video are a beginning.

I would like to see what you all are thinking about it first
To be honest I don't know if the fast guy is actually faster in that video but it shows the understeering very well and if I can get rid of it in ONE corner I can apply that on the whole track and will be faster in general as the fast guy gets around the whole track almost 2 seconds faster..

@Kek700 doing that seems like a "workaround" for the problems you see in the video. If you don't lift the throttle completely the car won't just brake as hard as without throttle. So I think it's some kind of "extra brake modulation" plus you don't have throttle on/off, like the "slow guy" (me) in the video

Will try that too!

 

[Mr Deap]

Online, because of the netcode, looking at player position & speed can be a bit misleading depending how large is the player ping.

Looking at your racing line, the first apex of the chicane is at the wrong place. It kind of screw the line for the second apex & it make you exit too wide making the trajectory longer than it should be.

Racing line is about taking the shortest route. Speed is a second matter.

 

[Kek700]

That is absolutely true, i know that from experiencing it as you have just said.
And when i have had a look at a lap using replay you can see it also, it
may cause more problems than it solves.

It is much easier to do in a real life scenario. I used to compete in front wheel cars
without the luxury of abs TC and it had an open diff so i used the brakes a lot to compensate
( i was a lot younger)

Unfortunatly at my age being low on dexterity is a problem, the more youthful should be
able to over come this, i think!
I will be interested in the outcome.

 

[Kek700]

I have done what your video shows over a full lap and all my entry , mid corner , and exit speeds
are virtually the same as someone 2.5 sec quicker, which totally baffled me.
So maybe Mr Deap has a point.

 

[Mr Deap]

Sometime an unbalanced setup may lead to erratic racing line. You have to look at both. If the car felt good using that line, it's a setup issue basically.

 

[RasmusP]

Sometime an unbalanced setup may lead to erratic racing line. You have to look at both. If the car felt good using that line, it's a setup issue basically.

It's fixed setup (ok, fuel, tire pressure, brake bias are not) so I think we can rule that out?
And for me it doesn't feel good. It's heavy understeering

 

[BhZ]

It's fixed setup (ok, fuel, tire pressure, brake bias are not) so I think we can rule that out?
And for me it doesn't feel good. It's heavy understeering

The car will always understeer because it's FWD. The more you accelerate, the more understeer you'll get. Trailbraking and brake bias are the only things that can help you since the setup is fixed. It requires a bit of practice, so don't expect to be able to do it quickly.
EDIT: also use better the throttle, sometimes flat out is not the best choice.

 

[Mr Deap]

With ABS I floor the brake fully & quickly. I also make sure that my steering is straight before flooring it. If you have your wheel turned a bit to the corner, you get less grip available from the tires.

If you turn without releasing brake pressure, you automatically get understeer. You can brake sooner & release the brake slowly as you turn in.

Car positioning is very important to get good laps. Smoother isn't better, you only need to be smooth when releasing the brake & steer in at the turn in, but timing need to be quick.