245/40/17 ZII Star Specs on OEM Wheels..Need advice please
 

I'm sure this has been answered before, and I've been reading through these forums, but time is running up & time to spend searching is running short.

To the powers that be, please advise:

I picked up a set of OEM Wheels last night, so now I have two sets. One for DD, one for AutoX. The set i picked up last night, they need autoX tires on them and they need to be mounted, balanced n bolted on my car by next Saturday. :bonk:

I have a set of 245/40/17 ZIIs on my on 17x8 wheels, and I'd like to swap them over to my OEM wheels (I want to run in stock class).

I've seen people pulling awesome lap times on stock cars with 245 tires on RPF1s, but I read that this fitment works because of that +42 offset :iono:. Then I've seen guys running 235/40/17s ZIIs on all sorts of wheels. Then I've read through these forums that running anything above 225 on 17x7's is just asking for trouble. There seems to be no consistency in writing and it's all subject to opinion. :iono:

SO....do I find a garage and tell them to just pinch my 245's on these wheels and when they tell me i'm nuts I just say do it anyway or do I buy a new set of ZII star specs (225 or 235).

Thanks in advance for any advice! :thanks:

Read the tire specs and see minimum recommend width.

245 on a 7" rim just isn't optimal and not recommended. I'd stick to stock size tires for stock rims. 245/40r17 I prefer on at least an 8.5" to 9" rim.

They fit and work fine. You can run 5mm spacers if you want, but you'll be fine without as well. I run the spacers for peace of mind with my 235/45 on +50 in stock size. Search thru the C Street thread for more info.

yeah, I've seen guys running the star specs, sizes 235s and I think even 245s on 50 offset wheels...I'm assuming you're running the Kosei K4s or Kosei K1 TS?

A rep at tirerack mentioned something about the ZII Star spec rubber (stiffer side wall?) allows you to go wider than other rubber. I.E no one's running 235 or 245 hancooks on 17x7 wheels.

I'm on "chapter 3" of that c street thread. Great info there, 100+ posts. Should be a book in pdf format :p.

Anyone recommend a shop around san diego that will mount n pinch my 245s on these wheels? A lot of places wont mount these tires on these wheels for liability issues. C2 motorsports comes to mind as a local shop that "gets it". Any others?

Thanks for the responses!

I've seen 245/40 on stock wheels on a few different cars for CS. There hasn't been an issues yet.

Yes, I have the k4r wheels but the hankooks in 235/45. They work well for me.

I ran 245/40 RS3s last year on 17x7 RPF1s. It pretty well for me and my codriver.

If you want to run spacers, you'll need extended length studs. Those are a good idea anyway, the stock studs are soft and you'll probably cross thread them if you change tires often enough.

The sidewall is going to flex differently, but they're going to be round and hold air and provide enough grip to put you at the pointy end of the field.

Echo everything renfield90 said.

I had a little rubbing on when at full left lock with 245/40 ZIIs on stock wheels. Fronts will need high 30s to not roll over even with the stiffer sidewall of ZIIs. Rears can be ~30.
I didn't use an impact on my lugs when swapping, but still messed up studs and went with ARPs. I think both the stock nuts and lugs are crap. Get different lugs and you might get some more time on stock studs.