MorganB1

Does anyone know if there are any issues mounting a 255/40 R17 tire on an OEM 8” rear wheel? I currently have these tires on 9 inch rears, but my Nitto NT-01’s just came in and I want to swap-over what’s left of my Kumho Ecsta MX’s to the original (RSA) cup 1 wheel set and replace the decrepit old tires that came original with the car..

Will this set up work w/o issues?

Tire shop says it is ok...

ilko

You'll be fine. That's how I have mine, no issues at all.

MorganB1

Thanks for the confirmation ilko. I just got back with the new NT-01’s and are they ever sticky!

Will head back tomorrow to have them mount the Ecsta’s on the other set. They are still in good shape for street use.

Track day on Monday!!

CWay27

255 on 8s is how it came stock from Porsche. No problem at all. I also got the nitto and very pleased about them although they are very noisy on the highway. These tires like a lot of negative camber. I run close to -3 all around and after a great day at the track + highway driving to get there, the tires still show like new and are wearing evenly.

Good luck!!

MorganB1

CWay27, thanks for the re-confirmation. I never noticed the RSA’s came with 255’s in stock form on 8’s. When I bought mine, I put on my set of 9” rears right away and promptly stored the originals. I saw today that they have the same size rear tire during the swap. Too bad for the original tires: a set of Yokohama AVS Sports with 90% tread left and looking brand new! But manufactured in 1999, so I felt they needed to go… Previous owner hardly drove this RSA in that period of time.

You are right about the Nitto NT-01’s! I’m another believer…!!!

After mounting yesterday, was out today scrubbing-in the tires and after some miles of “new-tire” greasy feeling during hard cornering, they really began to hook-up nicely. Did a few heat cycles and let them cool down in between. By the end, it blew away my previous levels of road tire grip!

I’ll need to see about dialing-in more negative camber. I think the car only has a modest amount, if any, in its lowered form and I need to get it aligned anyway. Looking forward to Monday.

Cheers!

Don Nguyen

That's weird that people on here would prefer/run a 255 on a 8" wheel.

I would consider that an oversized tire for that wheel width. Even a 245 on my 8.5" wheel seems pretty "squared" off on it.

I would think that you would cause the tire to kind of bubble a bit, being on such a narrow wheel, causing your performance/handling to go down.