P40vic

Just wanted to let you guys know that Craig Wilcox over on the scca sts forum is trying to put together a custom order of Slipstreams in 15x7.5 4x100. Some of the stock class mini guys put an order together previously for custom 16x6.5 slips so this can be a reality if there's enough people. Offset on the 7.5s hasn't been specified yet but I'm thinking 38-40 would be perfect for the front, I'll probably get some other 15x7s for the rear.

Zzyzx

The offset is going to be VERY important here on the front struts... theres bairly enough room for a 15X7....... Though if worse comes to worse a set of spacers should give enough clearance. (as long as you dont mind your wheels sticking out of the fenders abit.

P40vic

spencer-are you on 6.5s or 7s now? I'm on 6.5s at 38 and there's quite a bit of clearance at the inner edge of the wheel. If my math is right a 7.5 at 38 keeps the tire tread in the same place but some more bulge on the inside and of course the wheel edge moves .5" closer to the strut.

It surprises me that so many of the 16 & 17" rims have 40+ offset in 7 and 7.5, but I guess there's a little bit more clearance between the wheel and strut as the diameter goes up since the strut angles in a bit.

Boilermaker1

iTrader: (16)

Offset is huge, not the fronts, the backs. You need to clear the front of the A-arm.
16x8 +38 fits, barely, I can maybe stick a finger between the arm and the rim.... so drop 1/2 an inch off that diameter and pull it out a little bit. I'd say you're gonna need 38 or less. Get your fender rollers ready.
Fronts.... bleh, I've got 3/4". This isn't going to be doable with stock sized springs because you'll need to cut the spring seat off, but with GCs or coils, piece of cake.

Zzyzx

I have 6.5's... That I'm currently trying to sell to some one who doesnt know better.... Looking to pick up some 15X7's. Though I may keep the 6.5's around and slap some RA1's on them for track days.

P40vic

Boilermaker1-tell me more about your front clearance number. Your 16x8 et38 has 3/4" clearance to the strut? If so, I'd sure think a 15x7.5 et 38 or even 40 would be ok. I'm running 205/50/15s which are pretty short and nowhere near the spring bucket, but I could see how wide & taller tires would come closer.

I hear ya on the rear clearance, but I'm going to stick with 15x7 there which is a proven fit.

Chris

Boilermaker1

iTrader: (16)

<---- add a little more camber to this picture

I'm using 225/45/16s, which is a give or take 3.5" sidewall, and there's only 3 1/8 to the spring bucket.
Rears, are so tight its not funny.
15x7.5 same spot is a 43, so a 38, you can knock that 3/4" out to an inch, BUT you need to clear the crash bolt bracket. Which I don't remember it 15s are capable of doing.

P40vic

Man, a picture is worth a thousand! Thanks for this great post, very helpful to see what other rims look like.

Yeah, the front strut ears, I was thinking about that a few minutes ago, got 14" winter alloys on right now and the inner diameter of the rim would probably hit the top edge of the ear if it were a wide wheel. Gonna put the 15" race wheel on tomorrow and take another look.

The 225/45/15 hankook will make this all even tighter but if it's any good I'd be willing to do spacers to get it on there.

Boilermaker1

iTrader: (16)

Check the rules, but I don't think you can roll fenders in STS. So make sure on that when you size those rear tires and think about spacers.

Pete W.

iTrader: (1)

Per last years rules you can roll fenders but it's ALWAYS a good idea to double check first and if the rule book confuses you email Doug Gill at dgill@scca.com for clarification.

Pete W.

iTrader: (1)

Section 14.2 in this years rule book say that you cant cut or flair the fenders but you can roll them.

P40vic

FWIW, I just finished measuring up the front clearances using carpenters squares on the wheel mounting surface. The backside ID of the wheel has to be at least 14" diameter in order to clear the OEM strut ears. My 15x6.5 et 38 Enkei measures 14.6" diameter in the back so a wider 15" wheel with similar wall thickness should be ok. But wheel weights too far back might hit.

As far as lateral clearance, the closest point is the tire wall to the steering arm base, .84" for my hankook 205/50. Based on Boiler's 16x8 and my measurements, I'd bet the SSR 15x7.5 et43 would fit with 205/50/15 but clearances would be around .4" or so. Less offset would be gravy.

The 205/50/15 is short enough that there's lots of clearance to the spring bucket.

Clearance in the rear is a different story for sure.

Axxe

iTrader: (1)

Rota is awesome. On the SCCA the E30 guys have a GB going for 16x8 ET 20 Slips. Perfect fit, and cheap too, 550 for the set.