who here has used both wheels for tracking and if so which is better. There has been articles in the past that talked about how much better the 18's are on the track, however, I wonder if the 19's were aftermarket with a different offset that affected the scrub radius and made things worse, but not because of the diameter?

 

All I am going to say is 18's PERIOD.

-Alex

 

I have tracked with both stock hollow twists, gt3 look wheel for the tt that came on my Turbo S, all in 18 and with street tires like Pilots Sports and Conti's. No problem at all except for some loss of grip toward the end of my session.

No major scrub on shoulders on the above wheels/tires.

A few weekends ago I did a 3 day event with 19's and MPS2's that had 4-5 k miles on them. By the end of the event, All four shoulders were badly scrubbed/bald.

Not sure if this was due to the 19 wheel or the fact that my driving has gotten better and faster. When on the 18's I was in the green beginner group and now I am typically one or two groups up from that. The track was also a much faster track with high speed sweepers vs. the more technical track I had been to while on the 18's.

 

I have a 997 GT3 and have run both. Greatly prefer the 18s. The 19s tend to be very twitchy, especially at high speed. The 18s are more compliant. The additional sidewall, I believe, gives you better feel for the car. Z

 

I think the 18" wheels and tires, as a combo, may be lighter....and to be fair, the extra sidewall may make handling actually better....at some point F1 teams could lower sidewall and they don't/didn't....they are all standardized now, but if shorter sidewall was better for track, I cannot imagine F1 would not be doing it.

Jeff

 

this coincides with an article that I read years ago, where they tested a 996tt with 18" ps2's and then installed 19" ps2's, and the cars handling got worse even though they kept the overall diameter the same and offset the same for both sets.

 

https://www.6speedonline.com/forums/...9s-vs-18s.html

post #12 has a link to an article...maybe helpful, didn't read the whole thing yet?

 

yup, that is the other article I remember now...

http://www.europeancarweb.com/tech/0...res/index.html

 

Pilot Sports are useless on track, I guess you think it works ok until you have tried some proper rubber...