RX7Club.com - Mazda RX7 Forum - Rubbing issue on track (FD)

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You shouldn't sweat the diameter that closely. The stock S01 actually had a manufacturer posted diameter of 25" even.

Ah, I understand. The 9.5" wheel was Tire Rack's measurement tire. There are some people who subscribe to choosing a narrow tire for a give wheel width, but I think that's a bit overrated.

That said, any performance difference between the 255 and 265 has got to be small.

-ch

Is there any chance your toe links are getting sloppy?

Another possibility is that your tires are deforming enough in hard cornering to rub the well, which you won't get when you're on the street with much lower lateral g's. Dunno what the best answer to that is, except maybe to go up in pressure or find a stiffer sidewall tire.

Dave

I don't think so...I'm running M2 toe links and they (and their mounts) seem very sturdy. As far as sidewall stiffness, the PSCup are pretty stout but as I mentioned I was running a few psi low. This could be the whole deal; I don't know. But to be safe I'm getting a set of those spacers from CCW.

-ch

Quote:

Originally Posted by hyperion

Anyone seen this issue before?

For the record, I'm running 18x10 CCWs. As you can see, I have the M2 lower links. (Yes, I installed the spacers in the right direction.) The wheels do not rub under normal street driving. I am running zero toe and camber in the rear. The tire pressures were a little low--a few psi--due to cold ambient temps. I'm running 285/30 Michelin PS Cups. They are new and have been heat cycled.
snip-ch

FWIW, I run the same wheels & tires with stock links & trailing arms. I've only been to the track once with these wheels and I have no rubbing issues, no marks (of course my track buddy John Mag. says I'm still not driving hard enough :)). I was lowered to about 26" at the top of the rear wheelwell and rear camber was -0.8 and rear toe was 0. It looks like you have a little toe out.
-Ken

Quote:

Originally Posted by CMonakar

I recently spoke to a fabricator about hammering out the wheel wells. He said the most problematic area is tied into the end of the frame rails and will not move. I believe that is where the scuff marks are in the pictures above.

I wonder how difficult it would be to cut it back a bit and seam weld it. The trailing arms could be curved around the tire to provide more clearance. Obviously it would be a lot of work, but if it would provide enough room for 315s without doing any exterior sheet metal work it might be worth it.

Hyperion. What's the meaning behind your name? Any relation to structured finance?

I thought about doing the same. Even dropped off a set of arms and drawings off with Mitch Piper, but I ended up scrapping the idea once I had the 315s in hand. That is too much tire for the stock wells and the trailing arms would have to be rediculous. Not saying it can't be done, but it's not going to be easy.

I still don't know How Kevin W shoved those 315s in the stock wells, even with all that camber....