Need some help from some of the autox folks here.
I want to make the move to 285/30-18 A6's and need a little help sorting through wheels, offsets. to try and get a proven fitment.

I know that I'll have to do rear fender work. May have to run staggered offsets and widths.

I'm on Ohlins DFV's currently.

Any help or advice is appreciated.

Shoe

 

Looks like you have a IX?

You against spacers or a staggered setup? You could do a 9.5" +35 which is pretty easy to find, and just work from there on the exact fitment. Or you could stagger and do a +24 / +36 which I know will work as another guy here on the forums (broeli) has done with that tire. Do a search on his id. The 285's are a bit shorter than the 275's most people try so that definitely helps.

Or just go ***** out and get some 18x10's and wider fenders! lol.

I'm running 18x9.5" +33 all around and there's a little more room on the inside of the rear but not much. The front is very close and I run a 6mm spacer just to be safe. I ordered these to fit 275's all around with just a rolled rear fender but it's uber-tight.
I also have some +28's that barely squeeze in 275 hoosiers in the rear; but the fender is rolled flat for that!

 

I am not entirely against spacer or a staggered setup.
I would prefer same wheels all around for rotation purposes.

I know of some that run staggered widths and offsets with good results.

It seems like offsets in the 32 - 35 range fit fairly well on a 9.5 rim from what I am hearing.

 

I know guys that run RPF1's 18 x 9.5 +38 w/285 Hoosiers, 20mm spacer needed up front.

 

Why run a spacer? Why not get the correct offset instead?

 

because you can't rotate tires. lots of tracks will kill a certain corner on the car and it's nice to be able to swap that out easily with a rear that usually has much less wear and not just left to right.

also nicer to get a wider track up front if possible. and if you go 10's and make them fit under the rear you will have clearance issues up front in the ohlin springs/perches. you can run shorter springs up front but then you lose droop witch isn't a good thing on the evo. they are much happier with contact on all 4 corners whenever possible

 

I run that offset & spacer with 275/17s--you'll need some sort of small spacer (5mm?) to prevent the tire contacting the a-arm.

 

The +35 offset is required in the rear to fit. In front that will not work with the ohlins with any degree of camber.

Running an 18x9.5 +35 with the 285/30/18 A6 in the rear fits fine. The tire will rub the LCA a bit. You will also need to roll the rear fenders at a minimum.

For the front if you are running any appreciable camber (and you should be) then you will absolutely have to run a spacer. Running -3.0 or more camber will require a 15mm spacer with the ohlins. This gives an effective +20 offset in the front. You will probably have the OEM camber bolt set to the min position or set it to max and pull it towards min when torquing. This will provide enough clearance. Also with the A6 rolling/pulling or cutting the front fender is necessary.

Edit 18x10 +32 also fits. But this is second hand knowledge, I don't know the specifics. Evolutionary was running the Wedsports in this size. If you want to stagger the 18x10 can be run up front and 18x9.5 in back.

Have fun!

John

 

Sounds like if I did a 9.5 et35 in the rear and a 9.5, 10 et18 - 12 in the front that would be a good place to start.
The clearance issue in the front sounds to be camber related to the coil over correct?

Thanks for the info. I'd still like to hear what others are running. Is anyone running a big 17" with any success?

 

I meant a 5mm rear spacer along w/ the 20mm front. The fenders are rolled & the car runs abt -1.4 camber rear.

The setup works very well...

 

Thats what I run as well, I'm on 255/40 Z1's though.

What do you mean by a big 17"?

 

I meant 275/40-17. I would think a 17 might have a slight weight advantage. It may be offset by the better? grip of the 285/18.

 

As far as autox is concerned, if your going to be uber competitive you need to be on an 18's w/285 R-comps. 17's will def be lighter, both the tire and the wheel, but the grip advantage of the 18's is greater than than the advantage of loosing the unsprung mass. Thats what they tell me anyways...

We need to get Alwaysinboost in here, he's knows all about this stuff... he just made the jump to 18's w/285's. He has a set of CCW's on his car, I know they're 9.5's but I don't remember the offset.

 

I run 285/30/18 Hoosier R6's

I have 18x9.5 NT03's +40

I run a 3mm spacer in the rear (to clear trailing arm) You also have to grind off the casting flash on the arm and trim to metal brackets so you don't eat your tire!

I run a 25mm spacer in the front to clear the brembos. Since I run a 25mm spacer...I can also run 4 degrees of camber if need be.

I rolled the fronts and the rears. I also had to clearance the rear ward pinch weld in the front wheel well. That means BFH + grinder + new seam sealer + undercoating. I no longer rub.

Also with that much camber...your factory brake line mounting point will rub your inner fender "frame" per say.

If you'd like to discuss all the modifications that have to be made... PM me and I'll give you my cell number to explain further.

I would recommend the NT03's...

 

I've run 275/40/17's (mostly kumho v710 but recently hankook) on the stocker BBS's for 4 years in BSP (Las Vegas Region SCCA) PAX winner 2009, 2nd place all other years. Pinching them on those 8"wheels does slim down the true contact patch however. Didn't need to run spacers, but there's plenty of inner fender rubbing and trailing arm (rear) polishing...



just the poor man's route in avoiding expensive wheels