E36 Rear Tire size on RKII rims?

[dragonm3]

My fronts are just about dead (i'm down to the hard stuff). I need some tires and I thought I'd switch the backs to the front (I have 235/40 rear) and put something with more meat on the rear.

With 18" RKIIs, what sizes can I put on the rear?

[Spencer]

Whats the offset on them?

[dragonm3]

Originally posted by Spencer
Whats the offset on them?
I don't know. I'm sure the Tirerack guys know (they sell them). It's my hope they'll answer this question. Last time I didn't listen and it cost me $1,200.

[Jim@tirerack]

The RK-II is available in the 18X8.5 and you can run as big as a 255/35R18 on the rear with a possible fender lip roll.
If I can help let me know.

[dragonm3]

Thanks Jim,

I think I'll put 245/40/18s on my M3 then.

Now all I need to do is figure out if I want Yoko Avs or Kumho Ecsta MXs.

My thoughts on the tires are... Yokos are very responsive, break away is smooth, and generally feel great, but 'ultimate grip' is a little less than what I expected out of the tire (previously had them on 89 Rx7 TII).

I have Kumho Ecsta MXs on the rear of my car right now (pretty new tires, less than 2K on them). Grip is fannnntastic, but the other night I reached the handling limit (around a very well known corner) and the rear started 'hopping'. It really freaked me out. Hopping could either flip the car, or cause a total loss of control. I'd rather go with a slightly less grippy tire than experience hopping again - EVER.

What do you think (which tire you like better, hopping, etc)?

[Spencer]

245/40-18 is a TALL tire. I would either go 255/35-18 or 245/35-18.

- Hopping is not going to flip the car. Believe me, its going to take a hell of a lot more to flip the car.

- Hopping is not the tires. Its going to be either the suspension or road surface.

If you've got the MX's on the front, i'd go with the same on the rear.

[dragonm3]

Originally posted by Jim@tirerack
The RK-II is available in the 18X8.5 and you can run as big as a 255/35R18 on the rear with a possible fender lip roll.
If I can help let me know.
You might be able to help. What kind of deal can I get from Tirerack on those Tires? (245/40/18")

[Mode]

Again, I think 245/40 is too tall for your car.

[dragonm3]

Originally posted by Mode
Again, I think 245/40 is too tall for your car.

The stock tire size is 245/40/17... that's the same sidewall height on a smaller rim....

235/40/18 vs 245/40/18
25.5" vs 25.8"

That's less than a centimeter difference

+.15" on either side of the rim....

from 3.75" to 3.9" wall height.....



You really think that's going a problem? Why?

[Mode]

Even 235/40/18 is consided by some to be too tall. Let's compare stock to what you want:

245/40R17 == 24.7"
245/40R18 == 25.7"

That is ~ an inch taller. Acceleration will suffer and you may have rubbing problems. I can't think of any threads where I saw this size recommended. Just keep it in mind, bro.

[dragonm3]

<a href="http://www.inficad.com/~elvis/extra/CIMG0001.JPG"><img src="http://www.inficad.com/~elvis/extra/tn_CIMG0001_JPG.jpg"></a.>

Got 'em 235/40/18