[deacon_matt]

Hi,

I’m looking to go from 19s to 18s on my E92 M Sport as I find the ride too harsh.

I’m thinking about some 18” Japan Racing JR30, Hyper Black, in 8.5J ET35 front and 9.5J ET35 rear with 235/40 and 265/35 tyres. It’s on stock suspension and no plans to get coilovers any time soon. Would anyone have an improvement on this setup for 18s? Also has anyone done this and found a decent improvement in ride quality?

Thanks a lot,

Matt.

[TunafishE93]

Try going 225/40/19 front 255/35/19 rear on the 19". This will not only help the pocket but also ride and traction. It is actually better traction then 235/35/19 and 265/30/19.

If you do go with the 18" 225/45/18 and 255/40/18 will have better traction than the ones you list above plus better ride.

[deacon_matt]

Cheers for that reply, I had never considered doing that. Obviously it increases the rolling circumference, you don't see that as an issue? Have you ever done a similar thing yourself?

[TunafishE93]

With the 19" i just put on taller tires but i didnt think the ride was all that bad with the stock size. The ride is little better with the taller tires. I did it to raise the car alittle, i couldnt get a low profile jack under car without driving front on 2×4's and still was close. Now i still use the 2x4's but i have room to work the jack. Clearance wise you wont have issues unless you are not stock height. Plus i wanted to gear the car down a bit, really hard to tell the difference but i figured i went from 3.46 to about 3.33 in the rear. I have details about it here https://www.e90post.com/forums/showthread.php?t=1791203

[deacon_matt]

I see. I’ll have a look into increasing the rolling radius, I’m a bit skeptical as I haven’t heard too many people do it, but thanks and I’ll let you know what I do.

[tcphoto]

I went with 235/40/18 and 265/35/18 on my Style 189’s when going to Michelin non runflats. I have stock suspension and have been happy with the performance and esthetic for the two plus years I’ve had them.

[deacon_matt]

That looks very clean! Thanks for that. I’m also considering a square 17” setup because it’s cheaper on wheels and tyres, further improved ride quality and less under steer potentially. Let’s say I got a square 8J 17” setup, with 235/45 tyres, do you know what offset I would want on the wheels?

[TunafishE93]

Stock offset is 34 all around for 17" wheels.

[deacon_matt]

Thanks, I guess I can add spacers later if I decide I need to. Buzzing for some new wheels now, current driving experience is so compromised as I’m always thinking about the bumps and potholes which are everywhere (yes I already have non run flats)

[1Bad335turbopsi]

These are 17's with 235/45/17's up front and 275/40/17's in the rear....