GAZZ

Ok, that's a fair bit of punishment, so does not sound that bad.
Aim for 28psi hot.


Either way, if you go for a long lasting tyre it wont be so grippy.


Do any of you guys do sprint comps? That's pretty well all we do here.
Bit like an F1 Qually and everyone is on the clock, so no way my tyres would last one of your track days. One set is US$1900.

GT4_Driver

Sorry, but the tips here in terms of the right air pressure are all wrong. Don't lower it, but drive at least 36 psi on each tyre, better 37 on the back.

Lower air pressure destroys the Dunlop. Btw.: This information comes from Manthey Motorsport which developped the GT4 Clubsport together with Porsche and tested the series GT4 intensely.

GAZZ

With that pressure the contact patch will be smaller and the grip lower.

Inrev

Pyrometer readings gave me a lot more heat in the middle at those pressures.

GrantG

Yep, and the center of the treads come apart very quickly at those pressures. I imagine Manthey's recommendation is for the Nordscliefe which is quite different from most other tracks.

GrantG

Looking forward to having the RE71R's in stock sizes, so we can have a reasonably affordable tire that lasts longer (and most report is faster too).

TRAKCAR

So weird, not on RS, I have a new set of fronts because they won't wear. On second set of nicely wearing rears..

I run 33-34 hot and wearing fine on RS, maybe 1-2 PSI higher then MPSC2...

Not doubting anyone's input, just so hard to get a general consensus.

GrantG

Interesting, Peter. Have you also bought a GT4 yet? Would seem like the platforms wouldn't be too different with respect to pressures and wear...

orthojoe

That is exactly the pressures I was running with the GT3 based on someone with similar 'top level' info. This is what the tires looked like after 10 sessions at laguna seca run 1:37-1:38 lap times



At the end of the day, the car was understeering like mad. Then I looked at the tires and understood why.

The RS acts totally differently than the GT3 and GT4 in terms of tire wear. I suspect it has something to do with wider front tires and different spring rates.

BRNGT4

I can tell you for sure that this is a Dunlop specific issue. All the GT4,GT3,GT3RS cars running the dunlops exhibit the same center tread wear. The dunlops are faster than the michlens that's why we run them but usually we go through 2 sets of fronts for every rear. Track alignment does not solve this. We have cars running stock setup and cars running aggressive track. In all cases the center tread wear is bad.
We noticed that the rears on the GT4 being 295 on an 11" wheel are stretched and that the tread is flat. But on the fronts, 245 on a 8.5" wheel are squeezed. This results in a bulging center tread. The fronts when new look like motorbike tires. It's my opinion that the solution is to run a 9" wheel on the front with the same 245 Dunlop.

TRAKCAR

Hi Grant, sorry no GT4. I can be a bit confusing posting here on RS findings.. There is just more track use feedback here..

As Joe says even between GT3 and RS there seems to be a huge difference in wear rate front to rear. I have no experience with GT4 except following the threads.

265 fronts on RS may make the difference and I run -3 Camber front but the tires still wear outer edge. Just relatively much less than the MPSC2 but that's more due to the construction of the tire with the soft rubber on the outside only. The Dunlops are softer accros the thread and so wear more even. For this reason I prefer the MPSC2 because driving home there is always good thread left for wet streets.

RS tire wear both Dunlop and MPSC is 2:1 Front : Rear.
Opposite of 997RS and 991 GT3.
Funny my well setup 964 cords all 4 corners almost same session Nitto NT01.. How's ratio on GT4's?

GrantG

Interesting thought about the 8.5" wheels being too narrow - I hadn't considered that, but agree that camber doesn't solve the issue. Sounds like Joe experiences the same thing on the front of the GT3 with 9" rims also.

Wear for me is much better on rear axle - still on original set. I would say 2 or 2.5 sets of fronts for every rear set with Dunlops.

orthojoe

I would agree the same wear ratio with the 991GT3 as well.

O5C4R

what I experienced recently was running 28-30 hot in the fronts definitely reduces the tyre wear ALOT but also adds a little under steer. Running 36-37 hot resulted in less understeer but the tyres would have been shredded in 2 x 20 minute sessions. better to run at 28-30 hot and manage the understeer.

usctrojanGT3

Sounds like the same issue as with the GT4...springs up front might be too soft on your RS.