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Hello all,

this is a topic that has most likely discussed to death over the past years but - hope you don't mind - I would like to add another layer to it:

I am about to get tyres for my new OEM CSL wheels (as soon as I will have some clarity about the lifting of restrictions here in Ireland).

My understanding is that the E46 M3 CSL sizes - R19 8.5" front and 9.5" rear width rims - are (were) 235/35 R19 and 265/30 R19 respectively.

Now, the OEM sizes for the Z4M are 225/45 R18 (front) and 255/40 R18 (rear); I am thinking that it may make sense to actually fit 225/35/R19 (front) and 255/35 R19 (rear) to maintain a near-identical rolling circumference and at the same time not reducing the sidewall too much. I am aware that the tyres may be a bit stretched once the same width is fitted to a 1/2 inch wider rim

Any opinion / experience in this regard? Have any of you maintained the same tyre width while going up in diameter?

Thanks in advance for your input
Attilio

I use 265/35 rear which is close to OEM diameter and looks good imho.
(Also better comfort and better gearing on motorways)

The OE CSL sizes would be a better option, they are wider than your suggestion and so will offer more grip.

I think I ran 235/35r19 and 265/30r19 when I had them on mine - but I found them too crashy with the OE suspension, so replaced them with 224M wheels after a couple of months (did a part-ex with someone on the forum).

If I were to go to 19" wheels again, I'd definitely put bigger rubber on them - the 265/35 r19 sounds fine, but I'd even go as far as trying to get away with a 275/30r19 if I knew there'd be no rubbing.

You can but it won't leave much protection for the wheel. Standard sizes give your a bit more rubber on the road and a little more protection.

Ive run OE sizes 235s/265s for years on mine and its been spot on

Others do run different sizes and you can run a 255. Depends on the tyres sometimes you can get better deals etc

Interesting on the crashing I don't find any difference what so ever, my last car had H&Rs and im on standard sus atm and if there is a difference it is very negligible.

Thanks for your responses guys, really appreciated it!

I think I will go for 235/35 R 19 at the front and 265/35 R19 at the rear!

Thanks again
Attilio

Does anyone get arch liner rub on full lock with the 235/35/19 fronts? I seem to on my passenger side

MichaelK wrote: ↑Fri Apr 09, 2021 6:59 am Does anyone get arch liner rub on full lock with the 235/35/19 fronts? I seem to on my passenger side

Is your car lowered and are you running spacers?

For reference I'm on KWV3 (previously Eibach Pro) and no spacers.

I’ve just fitted some CSL wheels fronts 235/35/19 and I’m getting some rubbing on the outer front edge when I go round corners on the drivers side? Car was lowered by previous owner with H&Rs!

I’ve jacked the car up and it doesn’t rub on both locks but it’s very close! Would 225/35 on the front solve the problem?

Thank you all for your input and advice!!!