Hello,

Decided to make a new thread if there's some tips and suggestions to further improve the handling of a 996TT.



At the moment the car's handling has been modified with these settings:

- FVD PSS9's at quite stiff

- H&R sway bars front and rear, on their softest setting

- Toyo R888 tires, stock sizes 225 / 295

- Camber at front -1.X degrees (don't remember the exact)

- Stock wheels with 17mm spacers in back for looks

This is a good basic setup for tracking a street car...and fast too.

The car's easy and neutral to drive (and in a way must be so, because the main focus is on the 'Ring and wouldn't like to countersteer all the corners )

...so is the next step stiffening the sway bars a bit, more camber and wider tires ?

The questions:

Sways: Perhaps putting the rear sway from soft to medium-soft should help in corners ?

Camber: about how much neg. camber is possible without changing any parts ?

Tires and wheels: Does 235/40/18 and 295/30/18 harm the 4WD because a bit of overall diameter difference? or nevertheless is the GT2 235/40/18 and 315/30/18 combination still better? Will be driving with stock wheels with 8"/11" widths so hard to use a really wide 255/315 combination (or is there even a clearance for 255/35/18?) Also the spacers should balance the car a bit more in theory because the wider stance, for the front should I use the same 17mm as rear or a bit less?

So thanks for tips if you have any experience.
With these specs and my poor driving a lap of 7.50 at Nürburgring Nordschleife BTG Touristenfahrten is possible according my PBOX data, next year will hopefully be even better

The car's sleeping this winter but just added a Manthey-Racing LSD with 45% lockup...Interesting to see what it does to handling!? How much is the lock% in GT3 and GT2? Any idea?


An autumn pic before winter:



Can't wait for the spring here in Finland...And a Happy 2008!

 

Hay, Kaizu,

Nice car. Glad to find someone else who is interested in road courses! Is that the long course Nuburgring? I would love to drive that someday.

Your setup is pretty similar to mine. Here is my suggested list of things to do to get your lap times down:

1. Practice, practice, practice. Seat time will do you more good than almost anything if you don't have a lot of it already.

2. Tires. I use Michelin Pilot Sport Cups. Others prefer Hoosiers. These will get you several seconds per lap.

3. More negative camber. You will probably have to grind the front alignment slots to get more than about -1.5 deg, but it's well worth it. Rear is another story - haven't figured that one out yet.

4. Sway bars on stiffer setting. If your car is neutral now, then try bringing front and rear in an equal amount, or more in the front. It's easier to drive a car that pushes than one that oversteers. Then tighten the rear to balance the handling again. I run the PSS9 set on 3 front 4 rear for the track and 7 on the street. (Saving my teeth )

Jon

 

Kaizu

The LSD will provoke understeer, you will need to change your swaybar settings and probably some more.

The camber that you are running is not reasonable at all for the track. Anything below 2 degrees in the front is not really camber. Keep front camber more than rear, not viceversa, or at least, worse case scenario, the same. You will need to put camber plates if you are a bit serious about tracking. A 7:50 with your setup is totally insane, what track configuration is that?

As for tires, minimum 235/295, I would go 245/315. This rolling radius difference will not damage your 4WD, myth.

 

I would stick with the Toyo's since they are similar compound to the NT-01 but more advanced they likely have the same rear end grip or better as the NT-01 and the NT-01 is AWESOME with rear end grip, you'll feel much more planted than you will on MPSC.

Next-Camber, you can easily run -3 front and more, I may work my way up if I were you going -2.0 in front, then -2.5, then -3 and so on and keep the rear about .5 off of that (so -2.5 front would be -2.0 rear)

I dont think you've pushed your car hard enough if it's neutral with no understeer and you havent added the rear sway yet. Go on another track and learn the limits first, then drive well below that on the ring until you're used to it. Then work your way up.

 

Heavy

7:50s at the 'Ring is something Bergmeister would be very proud of in a stock 996TT.

So, Kaizu definitely is pushing the limits VERY far, or something is wrong with the logger.

 

He said it's possible, not that he ran it. I dont know what he's actually ran though, I was assuming he did like many do and analyze many sections of the track to see where you can improve and come up with a projected lap. It's pretty tough to actually get that time on a normal circuit, I'd imagine it would be very tough at the Ring.


But either way, I've never heard of anyone not complain about the understeer in a 996 TT.

 

I guess you are right, and I misunderstood it I bet, since that time is almost impossible to achieve with that setup other than by a 'Ring pro..and still.

 

Kaizu,
Nice to see you running your car the way it should be. Full soft on that rear bar is too soft I would only change one hole at a time but I would try to stiffen it up some. This makes it a lot flatter. More negative front camber is also a good idea. A slightly larger front tire will help also but I too have heard to keep the differences to a minimum. I will defer to Jean on this one as he knows much more than me. Good luck and try not to make too many changes at once and relearn the behavior of the car before pushing too hard. Good luck.

 

all above advise is spot on. 4 corner balance and camber plates will help.
I run -3.5 front and -2.5 rear. but this is a track driven only car. your set up is what we would consider a street set up.
Next real level up would be something like moton clubsport suspension.
Hopefully we will all run together over there in the not to distance future.
trying to set a a real road trip!!

 

Thanks for the comments guys. Pretty sure the handling improves with stiffening the rear sway bar as well as adding more neg. camber to front.

In my experience changing to Pilot Cups should give only a little more speed compared to Toyo R888 (I've driven with both, the Toyos are almost half the price so that's why using them ), they are quite okay.

Jean, thanks for the comment about the LSD.

And about the lap time, I stated in my first post that I'm talking about Nordschleife BTG, so that's possible! (but thanks for the comment, it isn't slow )

BTG means Bride-to-Gantry and that's the layout in Tourist Drive there. Because the roadworks and other traffic, it's hard to push under 8.00 min.
And of course, you can't drive there like you (and I) do in normal circuits, too dangerous.

 

That's seriously quick, I know some top guys in GT3RS's that struggle to get that kind of time, you any footage of your 7:50?

 

Yep I know...

But timing isn't that important there either...I just combined the better halves from two laps with PBOX. There's speed limits on roadworks so couldn't get a clean lap. But what is more dangerous is the traffic...too bad the place is so popular now.

By the way, the fastest BTG lap of amateur driver I know is another Scandinavian, Göte with his M3 CSL that has BMW Art Car graphics from the 1970's.

He did there a 7.42.5...He's so crazy guy
For example he goes to Fuchsröhre with something like 244 km/h on GPS



Maximum respect for the CSL too

 

Prices are about the same in the US. What sizes are you running?

Jon

 

Kaizu

My best (and only timed lap) was 8:30 there, I can see an 8:00 as my outmost potential best since it was was my first drive ever in my car and first time on the track as well. Those times are truly very fast (professional level) in your almost stock 996TT.

You are right, way too dangerous with the amount of crowd out there, I only stole one timed lap with great care, my two other friends crashed their 996s that day, one hell of a track for sure.

 

Jean,

Can you explain this? To my knowledge if the tire diameters front to rear are off by more than half an inch it will fry the center differential coupling?