Tyre Size for E36 M3 M double-spoke Style 22

[nzsapper 82]

Season Greetings all

 

I have just been to price up a new set of rubber all round for the 93 M3, tyre guy at Cooper Tyres did some quick calcs and said I will be fine to run 245/45/17s all round instead of the normal 235/40/17s saving around 20% on the purchase price?. 

Has anyone else done this with thier 3.0 M3 with non staggered Style 22s and if so did ti work?

Cheers

Paul

[eliongater 718]

17x7.5 et41? 245 seems too big and might look a bit balloon like, and is fitted to e46/36 17x8.5 wheels. According to this site what you have already (235/40R17) is the OEM size. Changing from that will alter your speedometer reading slightly. Personally I’d stick with the OEM size

 https://bimmertips.com/oem-bmw-e36-m3-wheel-opitions-specs/

[Olaf 3309]

Not to mention the 45 series changing your handling.  

Usually when you go wider, you go lower aspect ratio to remain at the same circumference.  The engineers set that car up as a package with thousands of hours of development time.  Unless you're looking to make specific changes, I'd suggest you stick with the stock sizing, as @eliongater suggests.

Here's a visual comparison of your stock size, and your tyre professional's suggested option:

Aside from the handling change (taller sidewalls adding 33mm to the height, more sidewall flex, and higher c of g), you can see it'll also gear it up, and nearly 99mm to the circumference (more than 5%).

Seriously, I'd shop somewhere else, where the tyre guy has a clue.  

 

[eliongater 718]

@Olaf I'd forgotten about the profile, I only got as far as the width being off, yeah 245/45 is way too tall, even for an 8.5" rim, it should be 245/40 if anything. I second that this tyre guy might not quite understand the nuances of tyres in this situation.

Edited December 15, 2018 by eliongater

[nzsapper 82]

Cheers Guys

Appreciated the advice

Think I will be sticking to OEM size. Like the Bimmertips site as well

 

 

[qube 3570]

Dont listen to that guy. that size is WRONG for your wheels/mags.

but in other news, why are you not running staggered wheels on your M3? It would be much nicer to go for a wider wheel especially in the rear. 

 

[KwS 2421]

16 hours ago, qube said:

Dont listen to that guy. that size is WRONG for your wheels/mags.

but in other news, why are you not running staggered wheels on your M3? It would be much nicer to go for a wider wheel especially in the rear. 

 

Early m3 with the DS1 wheels were a square setup factory. 

[qube 3570]

1 hour ago, KwS said:

Early m3 with the DS1 wheels were a square setup factory. 

I see, then I suppose it makes sense to leave it as is but also its not difficult to "upgrade" to wider wheels with style 24's and other M fitment wheels coming up for sale quite often from time to time for not a lot of money

[KwS 2421]

Let me do you a favour OP and buy those nasty old DS1 wheels off you...