Tire and wheel advice

[Ernie D]

Im currently running a set of 17x8 et18 ASA AR1 wheels and 235/45R17 Toyo Proxes r1r tires on my 530, the car is on the bilstien/H&R combo. I want to run 255/40R17 tires on my wheels.
Was trying to get advice on how wide of a wheel spacer I need to run to clear the struts and since the car sits lower, will I need to roll my fenders, for which Im trying to avoid doing.




Sent from my SAMSUNG-SM-G900A using Tapatalk

[zubbie]

Im currently running a set of 17x8 et18 ASA AR1 wheels and 235/45R17 Toyo Proxes r1r tires on my 530, the car is on the bilstien/H&R combo. I want to run 255/40R17 tires on my wheels.
Was trying to get advice on how wide of a wheel spacer I need to run to clear the struts and since the car sits lower, will I need to roll my fenders, for which Im trying to avoid doing.

Sent from my SAMSUNG-SM-G900A using Tapatalk

This is a hard question to answer. Certainly 255's will be close to rubbing or maybe rubbing but it all depends on tire choice and wheels. Likely the rears will be close. I run 255 rears on a rondell 58 wheel 17 x 10 et 15. No rub.

The only way to know for sure is to experiment.

[RedlineGoods]

You want 255/40s on all 4 wheels or rears only?

FWIW I used to drive 255/30R19 on 8.5x19 ET20 rims on the rear and nor rub at all. Now 265/35 on 9.5x18 ET23 and again - no rub. Stock suspension though....

[Ernie D]

You want 255/40s on all 4 wheels or rears only?

FWIW I used to drive 255/30R19 on 8.5x19 ET20 rims on the rear and nor rub at all. Now 265/35 on 9.5x18 ET23 and again - no rub. Stock suspension though....

I want to run 255/40s on all 4, I track my car quite often, and I would like to get more tire to the tarmac.
According to a tire/wheel calculator that Ive tried, the tire will be 10mm wider on both sides, so to compensate for it, I was looking at running 10mm spacers,but with that in mind, Im concerned about it rubbing the fenders, and Im trying to avoid rolling my fenders just to get them to fit

Sent from my SAMSUNG-SM-G900A using Tapatalk

[BleedsBlue]

Most would discourage you from running a 255 on an 8 unless it's a Hoosier or something else with a very stiff sidewall. Particularly in autocross you will notice the tire sidewall rolling over itself, it's not a precise or sharp set-up by any means.

I ran 9.5" wide wheels all around on my E34, with wide 255s (Hankook RS3), ET7 up front and ET22 (could have gone to ET12 easily) rear. Based on those numbers, I agree with your 10mm spacer assessment, but you may encounter fender rubbing unless you have enough negative camber. I ran -2 up front on GC plates, which honestly helped with turn-in much more than a wider front tire.

[Ernie D]

Most would discourage you from running a 255 on an 8 unless it's a Hoosier or something else with a very stiff sidewall. Particularly in autocross you will notice the tire sidewall rolling over itself, it's not a precise or sharp set-up by any means.

I ran 9.5" wide wheels all around on my E34, with wide 255s (Hankook RS3), ET7 up front and ET22 (could have gone to ET12 easily) rear. Based on those numbers, I agree with your 10mm spacer assessment, but you may encounter fender rubbing unless you have enough negative camber. I ran -2 up front on GC plates, which honestly helped with turn-in much more than a wider front tire.

I was probly going with federal 595 RS-Rs for my next track tire, a few of the other drivers that have bimmers also, has had very good luck with them, but they are also in e36 M3s, I have the only e34 in the group, the Toyo proxes r1r I was running were ok tires but not for the wieght of the car imo

Sent from my SAMSUNG-SM-G900A using Tapatalk

[BleedsBlue]

I was probly going with federal 595 RS-Rs for my next track tire, a few of the other drivers that have bimmers also, has had very good luck with them, but they are also in e36 M3s, I have the only e34 in the group, the Toyo proxes r1r I was running were ok tires but not for the wieght of the car imo

I agree with all of that, the R1R is objectively slower than almost any other modern, hot 200TW tire. What width wheel do the M3s run, though? I guarantee at least 9" to give the 255 a wide enough platform for sidewall support. If you are limited by class restrictions on wheel width, then disregard.

[Eero]

........

[ShapeShifter]

I used to run 275's on 17x9 no rub, no problem.

[Eero]

Offset? 275/40? Front also?

[BleedsBlue]

Offset? 275/40? Front also?

That looks like smaller than 275 up front. Also that is a narrow 275 (comparatively) to sit like that on a 9", something like the Fed 595 (based on their other sizes), Hankook RS3v2, Dunlop Z2* in 275, would all run too wide for a 9" wheel.

^That looks gooood, though.