[ctch22]

sorry if this is really obvious, but how do i find out which tyres will fit perfectly onto a set of alloys (no stretching, etc)

i need to buy a set for my 216 motorsport ones (18" 8J fronts 8.5J rears)

thanks!

[Bungle009]

Thats the same size as the MV3's so probably

225/40/18 or 235/40/18 at the front. (225 is BMW OEM fitment)
255/35/18 at the rear.

[doughboy]

Yep 255/35/18 is the OE rear fitment on a 8.5Jx18 rim.

But strictly a 255 is too wide for a 8.5J and they do look a little 'bloated', but your hand is forced by having to achieve a certain rolling radius across the model range.

To keep the RR standard you'll have to use 255/35/18 on a 8.5Jx18 rim., as this radius matches the front 225/40/18 on a 8Jx18 rim.

Dropping to a 245/35/18 will look better width wise, more like the front, but will reduced the RR too much and look odd as well as putting your odo and speedo out (read over, worst way)

A much better fit is on the 19" BMW rears where a 255/30/19 is used on the 9Jx19 rims (this radius also matches the 255/35/18 etc as do all other standard sizes on E9x)


But agree, factory fit is 225/40/18 and 255/35/18.

[Sir_Pigley]

Originally Posted by doughboy

Dropping to a 245/35/18 will look better width wise, more like the front, but will reduced the RR too much and look odd as well as putting your odo and speedo out (read over, worst way)

Putting 245 on instead of 255 changes the rolling radius and therefore the speedo reading by less than 1%. It would also change the ride height by a "massive" 3.5mm. If you can detect that with the naked eye you must be superman!

[doughboy]

Originally Posted by jdcampbell

Putting 245 on instead of 255 changes the rolling radius and therefore the speedo reading by less than 1%. It would also change the ride height by a "massive" 3.5mm. If you can detect that with the naked eye you must be superman!

1.1% less, so its +1.1% on the speedo, worse as the tyre wears, but yes a small amount.

You won't see the different RR of course, other than the slightly more stretched wall will look further 'in' under the arch.

Might work well with subtle spacers on an LCI though.

OP - you could possibly go to 245/35/18 a more 'correct' width for an 8.5J, might look ok actually.

[ctch22]

thanks for the help guys, think ill stick with factory fitment: 225/40/18 and 255/35/18

now to source a set of falkens...

[magic77]

I just fitted 255s to the rear of 8.5 and cant say they look out of place , will take pic tommorow and post

[parapaul]

225/40 and 255/35 Falken 452s on my MV3s. Rears look great - tbh much less and I think they'd look stretched.

[Dino355]

Why not use 245 40 18 instead? Rolling radius should be the same?

EDIT: Just done a calculation and it increases rolling radius by 2.67% so scrap that idea!

[ctch22]

another thing guys, would 20mm spacers be too much for the rears (cause rubbing)? or should i stick to 15mm?

[parapaul]

15mm works fine - have a trawl back through my threads and you'll find pictures. I reckon another 5mm wouldn't be an issue at all - but at 15mm they match the fronts offset now.

[Dino355]

It depends on which wheels you are using. On ET34 offset 20mm spacers at the rear would be fine, perhaps even at ET37 they should fit.

[ctch22]

Originally Posted by parapaul

15mm works fine - have a trawl back through my threads and you'll find pictures. I reckon another 5mm wouldn't be an issue at all - but at 15mm they match the fronts offset now.

yep ive seen the 15mm spacers you put on with your mv3s - looks very tidy

but like you say 20mm might also be fine, think ill try that if not 15mm it is

thanks for the input guys

[Sir_Pigley]

Originally Posted by ctch22

thanks for the help guys, think ill stick with factory fitment: 225/40/18 and 255/35/18

now to source a set of falkens...

Try something other than Falken. I have had 3 sets and won't be buying more. They are OK to start with, but they wear oddly on the outside edge and become VERY noisy (and before anyone claims it is because of the car, I have noticed this on two different E90 with two sets of Falken 452 - on one of the cars I paid for a full 4 wheel alignment unecessarily because I thought the wear may have been down to geometry issues)

I intend trying Vredestein next time, but they are out of stock at Camskill at the moment - they are usually the cheapest.

[ctch22]

oh dear, just made my mind up about getting falkens after id read all the positive reviews around the forum, now im confused again

i dont want them to get louder as they wear! have other people notice this too?

[Dino355]

In my opinion you pay for you get.

I've only ever used the following tyres on my e36 M3s:

Pirelli P-Zero Rosso - good overall tyre, very good dry grip, average in the wet, low noise
Bridgestone RE050 - excellent dry grip, firm ride, a little noisy but disappointing wet performance. Also used this on our 320d M sport e90 - very impressed with it
Bridgestone S02 - outstanding dry grip, almost as good as a trackday tyre, excllent in the wet but again very firm ride.
Michelin Pilot Sport 2 - the best tyre I've ever used, good ride, lower noise than the Bridgestones, amazing dry grip and impressive wet performance.

I am currently using Contis on both our e90s (run flats) and have been so far impressed with wet and dry grip although they are a little noisy. I've just ordered a set of Conti Sport Contact 3s for my 18s. From what I've read these are one of the best tyres you can buy.

Tyres are an essential part of how a car behaves and also feels. I've not heard many good things about Falkens and for the extra money I'd recommend you go for a premium tyre over a medium to budget range one.

You drive a premium car so why compromise on tyre choice? Look around on ebay - good deals are available on new tyres