I have a stock 2005 997S and I'm planning to buy a set of wheels and tires for DEs.

My current tires are Michelin PS2.
Front 235/35ZR19
Rear 295/30/ZR19

I was thinking of 18" factory lobster forks or something simple like that with Toyo R888.

Anybody know what size tires I should go with to keep the speedo and tire diameter correct? Thanks.

 

just stick with the stock 18 inch wheel and tire sizes. Many more track tire options in 18s, and you won't have to fool with the suspension to make sure they fit.

 

i have:

18x9 & 18x12 wheels

I run 245/305 toyos

work like a charm!

 

I have never tracked or autocrossed my 997 . . . but with previous experience autocrossing, using larger wheels was equivalent to using a lower gear ratio.

For example, on my S2000 I had 18" SSR GT1 rims. But when I autocrossed I used 17" OEM rims.

MonoJohn, I've been thinking about this same question. I recognize that you have 19" rims stock - so do Il. I have seen a lot of 18" rims for sale.

Anyone else have experience with using a 18" wheel on 997.1?

 

Phoenix,
Since my initial post I've heard from lots of guys that track their 997 S. They run 19s on the street and 18s on the track. More variety and cheeper rubber is available in 18" for the track.

You have to make sure the total tire diameter is the same with 18s as it is with your 19s so your speedo, ABS and other gadgets don't get confused. If you don't account for that you effectively change gearing.

The 18" wheel has a smaller diameter than the 19" so you have to put a taller tire on it to keep the total diameter the same as your street tires.

I just ordered wheels/tires in the same sizes mobonic mentions above.

Street:
235/35/19
295/30/19

Track:
245/40/18
305/35/18


Hope this helps.

 

Actually with the 18" sizes you will be putting more rubber down than the 19" sizes. Good choice I run the same sizes with Toyo RA1 tires....they are better and do not heat cycle out as fast as the R888's.

 

good choice

like mike said try to get some Ra1's

even though thet are 3 years old, they still are faster and last way longer than new 888's

or try to get some Nitto NT01

 

I will look into RA1s next time.
My first experience with the R888s will be next weekend at Road America.
Thanks.

 

mdrums & mobonic,
can you flip RA1s on the wheel to manage tire wear?
My understanding is that you can do that with R888s.

 

Yes you can flip RA1's and R888