TIRE / WHEEL Combo Vs Ride Quality

[Larz]

As I always remind people, I DID search first, LOL.
There are numerous threads about fitment and offset, etc. Nothing that I've read answers my question. I am in the market for 19 x 8.5 wheels for my 2009 M35. I currently have the stock 18 x 8 wheels with 245/45 tires. I will not be doing a staggered set-up. I reckon I can get 255/40 tires and keep close to the same ride height. I really don't want to change the suspension at all.
My question is this: I am concerned about ride quality. Will 19 x 8.5 with 40 aspect produce a more harsh ride?

[EniGmA1987]

it seems fine to me, but I have never had anything but 19's. The feel is good, and you get good feedback from the road without a harsh feeling. But thats just my opinion.
I recently switched off of the stock 19x8.5 sport rims because they were too damaged after 9 years of use and went with some TSW Cadwell's, which look similar yet better than the stock sport Enkei's and are a good price:
http://www.tsw.com/alloy_wheels_cadwell.php
I am running 255/35 on them and the fitment is really good, the edges of the tires are perfectly lined up with the edges of the rim. The ride quality is very nice on the Michelin's I got.
I have run 255/35, 255/40, and 255/45 in the past. All work well. The 45 height is the most "comfy" but gives too little road feeling and handling IMO.

[MY06M45S]

it seems fine to me, but I have never had anything but 19's. The feel is good, and you get good feedback from the road without a harsh feeling. But thats just my opinion.
I recently switched off of the stock 19x8.5 sport rims because they were too damaged after 9 years of use and went with some TSW Cadwell's, which look similar yet better than the stock sport Enkei's and are a good price:
http://www.tsw.com/alloy_wheels_cadwell.php
I am running 255/35 on them and the fitment is really good, the edges of the tires are perfectly lined up with the edges of the rim. The ride quality is very nice on the Michelin's I got.
I have run 255/35, 255/40, and 255/45 in the past. All work well. The 45 height is the most "comfy" but gives too little road feeling and handling IMO.

Could you post a pic of your car w/ those TSW's on? I want to see how they look like w/ the 255/35's on.

[DoN_BLaZe34]

245/40 would be the "ideal" size but if you want a slightly wider tire size then 255/40 is fine. I can't imagine the slight increase in rim size will be enough to affect the ride quality of your M.

[Li'l Truckie]

I run the OE Potenza's on my 2006 M45 Sport , 245/40-19. To me the ride is fine and firm, though I do have Tein coilovers and slightly lowered stance.

I would caution about too wide of a tire for the rim. It may not wear evenly across and cause more roll and give at speed. Though I would think 5mm on either side would make that much of a difference.

[EniGmA1987]

Could you post a pic of your car w/ those TSW's on? I want to see how they look like w/ the 255/35's on.

Ill try and get pics Sunday when I have some time.

[Larz]

Ty everyone for your advise! I'm narrowing my choices. I like the TSWs and the Vossens, but a mate of mine has a stunning set of INvcurves and I'm leaning in that direction. As of now, it looks like 255/40/19's on INcurve MBS10 19 x 8.5 (or 9) on each foot.
.

.

[MY06M45S]

I think those incurves will look pretty nice! I would not get vossens.

[Ilya]

I was going for Vossen CVT's and then I found the Incurve IC-S10's...

I talked to Joseph (owner of Incurve) and he said they are better than Vossen for reason such as that they are rated to withstand around 1,950lb per wheel as opposed to Vossen's which are only 1,700, etc.

Not sure if that's just his sales guy pitch or a fact...but...I decided it was enough for me and bout a set of 20x9 IC-S10's.