I hated MPSC's when I had them for my M3, but the new Porsche spec Cups are substantially better in the wet and with heating up.. Which tires did you get and how old are they? I believe they still make 2 different variants, the better ones being equipped stock on the new 997 GT3's, Stuart997GT3 and I got caught in the rain a few sundays ago and his car was solid as a rock on them!

 

In the door jam of the GT3 fr 29 cold rear 33 cold

 

I have raced the 996tt for over 6 years. Depending on the tire, I
need to run pressures in the low thirties to low forties, and these
are all DOT street legal tires, with wear ratings between 30 and
180.

 

I go with Onelap guy thats wher the rubber meets the road!

My opinion is that MPSC s belong on the track and a second of street wheels is a smart way to go.

Hey One lap guy ...do the Hoosiers R6s last as as long as the MPSCs?

BTW The guy at Fairfield County Motorsports know their stuff and great guys to work with.

Elliot

 

Marc: that is very interesting. The first generation MPSC Michelin warned not to use lessthan 32 psi on the road cold. Obviously the Gen 2 tire is reasonably different. As far as I know this gen 2 tire has only been available on the 997-GT3 and 997-GT3-RS.

Joe: I assume the tires that you ran in the mid forties were Hoosiers or similar? On the One Lap car we have found that the Hoosier R3S05 works best at 45-50 psi hot at the rear. We'll probably take 3-5 psi out for the R6 model. This is probably not a good comparison though because the car setup is so biased toward the One Lap and the MPS2 street tire. Mild springs and damper rates, and miled camber settings for the road transits.

Elliot: Nice to see you out here in the electronic abyss!
The R6 will not last as long as the MPSC. The MPSC is the longest lasting DOT R tire I have every seen. However the Hoosier is much more confidence inspiring on the limit and you will probably have more fun driving on it. Depending on your level of abuse/skill it is possible to get as few as 6 track days from the R6 before the cord shows

In case anyone cares I've become fond of the Kumho V710 which has very limited sizes but you can really ride it on top of the grip curve and it doesn;t bind up the car and slow it down at hig slip angles like the R6. Also of course it is way more fun than the MPSC. Admittedly I still have MPSCs on my 944T track car because they seem to last forever and My budget does not last forever.

 

OneLap thanks for your info...very educational

 

Interesting info thanks.. Im not an RA1 junkie, one might get that from my previous posts, but i absolutely love the tires.. What is your take on them? On the track they are fantastic, i have a set of shaved on my BBS's now, dont know how long they will last compared to my other street/track set but the grip/feedback should be marginally better!

Martin

 

OneLap,

very informative, My R6 do seem to slow down at high slip angles!!!
thanks for great info!

How about a couple of good pics of the winning one lap car and what has
been done to the engine,ie. stock internals?, what exact turbos or kit?
exhuast? suspension? sway bars, ride height, etc.??

thanks in advance.

Marty K.

 

I don't want to hijack this thread from it's intended purpose.

I'll start another thread a little bit later about the One Lap.

 

Hi, OneLap, the tires I found to need high pressures were indeed
Hoosiers, and also some more street-oriented tires that have
thinner sidewalls, such as the Yokohama AD07s. Kumho 710s
needed much less pressure. I prefer the Kumhos to the Hoosiers.
Joe

 

I have 2 sets of rims so I intend to change back to the pilot sports for daily driving.

I am very suprized with the low pressures of 32/34 and 32/36 most folks are are reccomending, that seems low. I followed the link to the factory Michelin information and read the whole thing. They recomend 32/36 f/r hot in the begining of the document and then recomend 32-34 fronts, and 37-40 rear tires in the 996 model specific information on page 42 of the document. That seems more reasonable??

 

Live2shift: Correct tire pressures can vary considerably depending on the vehicle, and on similar vehicles will vary alot depending on ambient weather conditions, track surface, tire width, tire air volume, suspension setup, vehicle weight, alignment, and most of all driver skill and driver preference. That being said some of the lower pressures cited here seem rather low to me. Then again the specifaction for the 997GT3 is also low so my advice to you is start on the higher end of the scale and if tire wear allows reduce the air pressure until wear on the outside shoulder becomes excessive.

 

Sorry for the candid question, but how do you assess wear in the course of a track session ? Tread depth or do you need a pyrometer ?

 

Just look at the wear visually, if you are destroying the verymost outer edge of the tire and in particular if the tire is rolling over on to the sidewall then it does not have enough air pressure in it. Obviously an overheating condition can be checked with a pyrometer but most folks don't have one and unless you come into the pits right off a hot track lap the temps won't be true hot temps anyway. don;t forget alignment and soft suspension can be an issue here too.

 

Reporting back in from the Track:

I did my track day at New hampshire Speedway with my brand new pilot cups (2002 date code) and and I was scared silly the first run (approx 10 laps). Once they got more heat into them, and I dropped the pressure to around 32f/37r hot they were very consistent and not that different than my Pilot sports but I think they are more predictable at the limit, not letting go so abruptly, but slipping nicely. They certainly appear to be very Durable. Today was 85 degrees and they were smokin! The tires are so stickly that they picked up tons of misc. rubber debris from the track and driving them home on the highway was really noisy with some minor vibration. AI think they are great for the short NHIS track where there is nonstop braking and turning. I will be trying them at an autocross next and report back.