[jbertino]

Would switch from a 18inch rim to a 20 inch really make a big difference on performance. Would I be able to notice it. Also the same for a 19inch rim

The rims are both about the same weight as the stock ones the 19 are actually a little lighter because I'm getting rid of the runflats

[theinfamousdrew]

Yikes!

I cant really speak in terms of performance but, the ride quality would be greatly reduced.
With 19's or 20's you are reducing the side wall of the tire which reduces the amount of space between your rim and the road.

With my M3 I bought some OEM CSL wheels which were 19's. The ride was extremely harsh. I tried 3 different sizes and brands and none of that made any difference.
I ended up selling them and buying a set of OEM E9x M3 wheels which were 18's

Hope that helps


ps. you might want to post this in the wheel section, you will prob get a better response.

[ihc95]

Increase in performance? If anything getting 20'' wheels will slow the car down, not because of weight but because getting bigger wheels essentially has the effect of gearing the car higher. The max I would go is 19'' with some 35 and 30 series tires.

[mithiral67]

http://www.caranddriver.com/features...sted-tech_dept

Best info I can find on wheels size on performance.

Here is one on dyno results.

http://www.6speedonline.com/forums/9...orsepower.html

[venom3469]

With less rotating mass, comes better acceleration and power.

[bigdnno98]

I went with 19" wheels a long time ago for looks and I regret it every day because of the performance loss. Matter of fact I have some mint matte black miro 111 for sale if you want them. LOL