I'm evaluating wheel options for my '87 Carrera. I recently got a set of 7.5"x17" and 9"x17" Rota Fox (Fuchs copy/replica), but I'm now considering my old (original) 7"x16" and 9"x16" Fuchs for the track rather than the 17" ones. The Rota Fox rims are pretty much exactly twice the weight of the 16" Fuchs. That means over 50 lbs of less rotating mass with 16"!

I have even thought about 15" wheels, both to get the rotating mass down, but also to have smaller over all diameter wheels for a better over all gearing. I have 930 callipers and rotors, so 15" is not a problem for brake clearence. 15" might be a problem for tire selection...

Both Kuhmo and Hoosier have a decent selection of 16" tires, but I have yet to find a matching set of 225's and 255-275's with apropriate profile in 15".

Any thoughts or ideas about this topic?

 

Hoosier makes a 275/50/15 that a lot of the racers run on custome 15s. I run 7s and 9s fuchs (maybe 8s and 9s after the SP event). With 225 and 245 RA1s or Hohos.

 

I think I recall that Fuchs replicas were a no no for track use, due to a tendency to break.
I do like your idea of lighter wheels, but ran 17" Fikses on my 1984 Carrera, so can't help you on the 15" question. I know there has been a lot of thread material on that topic.

 

I think that tire is 275/35/15!
Needs a wide 15 inch wheel.

The 7&9 Fuchs are good for 245 or 265 rears and 225 fronts

If you get the 944 8" Fuchs up front you can use 245 front tires also.

On the street the 17 inch wheels have an advantage as there are few (none?) options for 245 or 265 tires for the street.

Greg

 

I really liked the Fuchs 8s&9sx16 I ran on my SC. Great light wheels. As I recall I ran 245&285s which I liked. Hoosiers.

The current favorite of the fastest guys racing are the 15s built by Jim Buckley. Becoming very popular.

 

Will 15" wheels work with 930 brakes?

 

Nah, they are running 15" Jongbloeds..

 

15" Fuchs 7 & 8 & 9 will, though w/ the 7s a spacer or some trimming of the caliper face is necessary.

W/ others probably but it will depend on the design of the back of the spokes

 

Man, I need to reread my posts before pushing the go button
The Hoosier site says minimum 9" wide for the 275/35/15 tyre. I understand that many have had to reroute their oil lines on the right side to run these too.

 

Besides the oil line, which is usually pretty easy to move around, a 275 can interfere at the trailing arm, it depends on the wheel width and o/s

This is a 275 on a 9.5"ET19 wheel, the wheel is perfectly centered in an early Carrera rear wheel well.