Newb's Tuning of Audi TT 3.6 Quattro - please comment!

[Evtim]

Hi everyone. First, let me thank to all of you for all the valuable articles and guides you have created about customizing the cars. In the case showed below I have used mainly the advices of Scaff’s guide to tuning (great job Scaff, thanks!).

Please, read below my reasoning while I was adjusting the car and comment. If somebody wants to try the car with those setting you are very welcome to give feedback. Along the text I will ask a number of questions to which I would be very happy to receive an answer or a hint.

So, here goes:

Aim: - to win Tuning Car Grand Prix in the Professional hall.
Now, one of the tracks that gave me big headache is the Apricot Hill (reverse), where you always have at least one powerful RUF car among the competitors (those are fast!)

So, I bought the Audi TT 3.2 quattro (4WD) and bought everything for it. At the end you have ~420 HP and the game awards you around 130 A-spec points if you win.
For a newb in GT (only played for 2 weeks) that is ample challenge I think.

I took the Audi on the Apricot Hill course and started testing from point 0 (everything on defaults settings).

First impressions – the car handles horribly, massive under steer. The gears are too short – only 175 km/h maximum speed on the start/final stretch.

Before I started the test I put the Drive aids to 0/0/3 and I put the VCD from 40 to 25.

Question: it says that the closer you are to 50/50 on the VCD the cars turn with more difficulty, so that was a logical place to start. What are your comments on this? I did not notice dramatic improvement of handling but I decided to keep it 25 anyway.

1. First correction – the gearbox. As suggested, I first lowered the final ratio to the minimum, then slide the Auto settings first to 25, then to 1 and adjusted from this point. I finished at Auto setting 12 which let me reach maximum speed above 230 km/h and you just hit the red region of the revs at 6th gear when you have to break for the first corner.

Question: I could reach more or less the same gear ratios with higher final settings and lower Auto settings. Is there a reason to choose one way or the other? I followed blindly the recommendations of people from GT Planet, but I cannot comprehend the reasoning behind it.

2. The under steer was horrific so I looked at my notes for the most effective tweaks to tackle this.
Hypothesis – the LSD has too high settings. It was 10/40/20, so I changed it to 10/30/10. Result: Significant improvement (it was rather dramatic change). Good!
OK, getting better but still away from perfect.

3. Dampers and Anti-roll bars. First – put all dampers from 8 to 4. The car handling improved again; much smoother ride. Under steer is still an issue. Then I played with the roll bars for quite some time and arrived at 2/5 (from 6/6). It looked a bit extreme, but it worked. I was hoping later to improve handling further and be able to decrease the margin between front and rear roll bars. I also followed the advice to have the rebound higher then the bound. Tried with bound 4 rebound 6 but somehow it did not feel well. 4/5 was better so I leaved it at that.

Question: Does the 2/5 roll bars seem too extreme? Would you suggest using the dampers to try minimizing the under steer. I tried decreasing the front values with one “click” but somehow I could not detect improvement (maybe due to my limited experience in GT and rather inconsistent driving stile)

4. Breaks – that was a tough one and I still cannot say I have optimized it. First – the weight distribution of the car is unknown. Since the default settings for the springs were 8.4/6, that suggested that the weight is distributed 60/40 % (F/R). In such case considering the weight transfer during braking I decided to try stiffer front brakes and went for 8/4. Now, on straight line I had better braking distances but the car had to be straight. If I tried to brake and steer (a bit) during turn-in the rear would “whip”. Since I am a newb I have to brake during cornering from time to time, so I decided to go for equal brakes again, only a bit higher than the default. So 6/6 instead of 3/3. And I am convinced that this can be much better.

Question: I see in some of the manuals that people often suggest such “unbalanced” proportion of braking F/R = 2/1 even 3/1 or more. However, if I look at the posted tuned cars on the board I very seldom see such proportions. Any comment would be welcome. Of course, the “whip” of the rear can actually help turning (the front was still a bit stiff at that point) if you manage to control it, so I still doubt my decision to go back to even distribution. And besides, does my observation contradict with what is known? I though that if you want to decrease under steer you should put the rear brake stiffer, not the other way around. Anyway I did not want to correct under steer with brakes, just to have reasonable braking distances without loosing control.

5. Next I tried tinkering with springs and ride height. Now, since the dampers and roll bars were softened perhaps I needed to INCREASE the ride. But I also wanted lower ride for better stability and higher speed at corners. So I stiffened the springs (retaining the ratio F/R) and lowered a bit. The car was a bit faster then and I did not dare go any further.

Question: Do you think that the under steer problem would have gone easier if I had adjusted different settings for the Ride Height instead of relying only on dampers and anti-roll?

6. Camber and Toe – I tried decreasing the front camber to 1.5 but the result was negative, so I decided to keep Camber and Toe unchanged.

Question: Do you think that Camber and Toe would significantly improve the car if I got the right numbers?

7. Lastly, I decrease even further the LSD acceleration help from 30 to 25 and called it a day.

Summary: With all those modifications I was able to do 1min 32 sec lap. I tried the race itself but I could not beat the competition due to my inconsistent driving. But I think if I learn the track well and optimize the way I am handling cornering I should be able to win.
Only the RUF’s give me hard time – all other cars I can beat with my meager driving skills.
As someone on the board said once the most “customizable” part in the whole system is the driver! And I clearly have a room for improvement of myself!

Summary settings:

Suspension: F/R

Spring rate: 8.4/6 --> 9.9/7.5
Ride Height: 129-->120
Bound: 8/8-->4/4
Rebound: 8/8 -->5/5
Camber: 2.0/1.0
Toe: 0/ 0
Stabilizers: 6/6-->2/5

Brake controller: 3/3-->8/4-->6/6

LSD: 10-->10
40-->25
20-->10

Driving Aids: 0/0/3

Transmission: Auto Setting 12, final 2.500

Down force: none

VCD – 40-->25

 

[Greycap]

Audi TT 3.6 Quattro? I take it as a typing error as you mentioned 3.2 in the text part. Right, let's answer these questions.

Question: it says that the closer you are to 50/50 on the VCD the cars turn with more difficulty, so that was a logical place to start. What are your comments on this? I did not notice dramatic improvement of handling but I decided to keep it 25 anyway.

It is more noticable when you begin serious tuning with the front LSD. As a short summary, more power to the front helps in slow corners as the front wheels pull the car into the desired direction but in high speeds you'll want less power in the front to reduce understeer. Try to find a balance.

Question: I could reach more or less the same gear ratios with higher final settings and lower Auto settings. Is there a reason to choose one way or the other? I followed blindly the recommendations of people from GT Planet, but I cannot comprehend the reasoning behind it.

I never do the "tranny trick" you just mentioned. It gives damn odd effects sometimes. I only use the stock Auto setting (unless it's just ridiculous, in which case I'll adjust it by maybe three clicks) and do the rest of the tuning "by hand". I always prefer traditional gearbox tuning to the tranny trick. That's the way for the best results.

Question: Does the 2/5 roll bars seem too extreme? Would you suggest using the dampers to try minimizing the under steer. I tried decreasing the front values with one “click” but somehow I could not detect improvement (maybe due to my limited experience in GT and rather inconsistent driving stile)

Not extreme at all, it is a good help in combating the understeer. Actually very good stabilizer settings. For reducing understeer via the dampers, try bound 3/4 and rebound 6/8. It should work.

Question: I see in some of the manuals that people often suggest such “unbalanced” proportion of braking F/R = 2/1 even 3/1 or more. However, if I look at the posted tuned cars on the board I very seldom see such proportions. Any comment would be welcome. Of course, the “whip” of the rear can actually help turning (the front was still a bit stiff at that point) if you manage to control it, so I still doubt my decision to go back to even distribution. And besides, does my observation contradict with what is known? I though that if you want to decrease under steer you should put the rear brake stiffer, not the other way around. Anyway I did not want to correct under steer with brakes, just to have reasonable braking distances without loosing control.

This depends very much on the car in question. Sometimes the 2/1 is the best solution because it keeps all wheels from locking up and thus gives the best handling under braking. Sometimes you can safely use, for example, 4/7 to make the car turn a little better without any fear of losing it. It depends entirely on the car.

Question: Do you think that the under steer problem would have gone easier if I had adjusted different settings for the Ride Height instead of relying only on dampers and anti-roll?

Maybe, but the best result is achieved by using them together. Very low is seldom good, I usually use at least 100mm of ride height, even on low sports cars. It helps the weight transfer, which reduces understeer. Lower cars are more stable, but stability often means understeer.

Question: Do you think that Camber and Toe would significantly improve the car if I got the right numbers?

Definitely. Another thing that will significantly improve it is taking all the driving aids off, they may make the car easier to drive (even that can be debated though, I think even TCS increases understeer) but also slower.

For a good bunch of setups for different cars of different power figures and drivetrain configurations, visit Mad FinnTuners Co. and you'll learn a lot. Be sure to read all the text in the first post. 👍

 

[Evtim]

Valuable input and advises, thanks man!

I switch off the driving aids before I started tweaking. Thanks to this board I already knew that the driving aids would "camouflage" the true behavior of the car.

Yesterday I did some more driving and I think I am very close to wining. I will definitely try tonight the damper settings you recommend.

When I finish the Tuning challenge I will buy myself a powerful rear drive car and try to tune it. So far, as newb I was relying on FF and 4WD cars only. The time has come for a RUF BTR or something similar.

Cheers!
Evtim

 

[Greycap]

You're welcome, I saw it as my duty to offer a hand!

If you have even slight doubts about your driving skill, for your own best stay away from the RUF for a bit longer, no matter how gorgeous it is. It's very difficult to drive. I'm a GT veteran with some eight years of experience, having golded and won everything possible, and the BTR still kills me in every other corner if I make even the slightest of mistakes. For a good, powerful (after tuning at least) rear wheel drive car I would recommend the latest Corvette or an FD body RX-7. Lots of power but also lots of controllability. 👍

 

[Mt. Lynx]

You can drop the ride even further!

And a tip: Instead of using the stabilizers to tune out understeer, take away the TCS alltogether and fine tune the LSD.
The car is 4WD, but on a racetrack you don´t have that much use of it, except during acceleration. This means you can set the VCD to the rear as much as possible, and also that you set the front and rear LSD up independently.
Example: Front: 5/5/10 Rear 25/45/20

Camber and toe are usually easy tricks to use for cornering stability and braking/accelerating stability.

 

[Evtim]

Alas, Greycap, I was suspecting that the RUF might be a bit too much for me at this moment.
You are right, better start with something not so demanding.

 

[Evtim]

Thanks Team666, I will try your tip ASAP.

Do you think this Audi will do me good on rally tracks then (with the proper tires of course)? I also have this monstrous Toyota you win when completing one of the special events. But it is so powerful, that I "use" it by selling it and buying stuff for the other cars.

I guess however, that I should have another quite different set of settings for the rally track.

 

[Greycap]

You can drop the ride even further!

And a tip: Instead of using the stabilizers to tune out understeer, take away the TCS alltogether and fine tune the LSD.
The car is 4WD, but on a racetrack you don´t have that much use of it, except during acceleration. This means you can set the VCD to the rear as much as possible, and also that you set the front and rear LSD up independently.
Example: Front: 5/5/10 Rear 25/45/20

Camber and toe are usually easy tricks to use for cornering stability and braking/accelerating stability.

Dropping the ride height may, no... it may not, it WILL cause more understeer. And if you say that the stabilizers should not be used in tuning out the understeer, you don't know much to be honest.

And sorry to say but that VCD and LSD combination will result in a car that wastes all (if it's not much) the power going to the front wheels spinning it off in a cloud of blue smoke and reducing the front grip even more, while making it hard to turn thanks to the stiff rear diff. As odd as it sounds, a stiffer front diff and a looser rear one give the best corner exits as the front wheels pull the car out of the corner.

 

[Evtim]

Dropping the ride height may, no... it may not, it WILL cause more understeer. And if you say that the stabilizers should not be used in tuning out the understeer, you don't know much to be honest.

And sorry to say but that VCD and LSD combination will result in a car that wastes all (if it's not much) the power going to the front wheels spinning it off in a cloud of blue smoke and reducing the front grip even more, while making it hard to turn thanks to the stiff rear diff. As odd as it sounds, a stiffer front diff and a looser rear one give the best corner exits as the front wheels pull the car out of the corner.

Well, so far every manual that I red indeed recommends the roll-bars as a very useful tweak in controlling under steer. That is why I started there after the other preliminary tweaks.

 

[Mt. Lynx]

Dropping the ride height may, no... it may not, it WILL cause more understeer. And if you say that the stabilizers should not be used in tuning out the understeer, you don't know much to be honest.

And sorry to say but that VCD and LSD combination will result in a car that wastes all (if it's not much) the power going to the front wheels spinning it off in a cloud of blue smoke and reducing the front grip even more, while making it hard to turn thanks to the stiff rear diff. As odd as it sounds, a stiffer front diff and a looser rear one give the best corner exits as the front wheels pull the car out of the corner.

Mind you, the VCD/LSD combo was an example, not an order. I haven´t even tried his setup for gods sake! But going for a stronger front than in my example is of course advisable... But on the other hand, LSD is always just a tip, as LSD is probably the most personal setting of them all, as it directly reflects your drivingstyle.
But a stiffer front LSD (than the rear) WILL give you understeer during corner entries. As always, a setup is a compromise of bad things.
And for the stabilizers, I was merely pointing out that he shouldn´t use only the stabilizers to tune out the understeer.
And no, lowering the car does not always end up in understeer, especially if the suspension is set up correctly. Now, I never "slam the car to the ground" as some would say. Infact, I usually don´t go lower than 70, even in a full blown racecar.

Thanks Team666, I will try your tip ASAP.

Do you think this Audi will do me good on rally tracks then (with the proper tires of course)? I also have this monstrous Toyota you win when completing one of the special events. But it is so powerful, that I "use" it by selling it and buying stuff for the other cars.

I guess however, that I should have another quite different set of settings for the rally track.

I have actually made a rallysetup for a TT, found here.