Upsizing wheels and tires

[msp]

I currently have an 08 M35 with 18" wheels and Goodyear tires. I would like to upsize to 20" wheels. Will the ride quality suffer too much or not that bad? Thanks for your input.

[jankenpo30]

I currently have an 08 M35 with 18" wheels and Goodyear tires. I would like to upsize to 20" wheels. Will the ride quality suffer too much or not that bad? Thanks for your input.

Honestly "ride quality" is such a subjective opinionated item that any answer you will get hear won't help you make a decision. Best thing you can do is try to find someone who has 20s on it and ride in their car.

For me, its the same. However, I have a sport and all my previous sedans have been riding on low pro tires. So far the M has done the best at maintaining stock ride feel. I run General Exclaim UHP which IMHO is best tire out there when you factor in price, noise, & wear.

[msp]

I was hoping you'd say that. The twenties look killer on the M. Thanks.

[CakeDaddy]

I currently have an 08 M35 with 18" wheels and Goodyear tires. I would like to upsize to 20" wheels. Will the ride quality suffer too much or not that bad? Thanks for your input.

You will sacrifice little to none of your ride quality; hardly enough to make a dramatic difference. Personally, I wouldn’t have it any other way! 20’s on my car was a no brainer. My car is lowered with 20's and rides like a dream. Going frommu OEM 18inch 235/45's to my current setup was nearly identical. Your tire choice is very important. I recommend getting a good set of tire (Bridgestone, Pereilli, BFGoods, etc...) Also, get the best balance possible. It took me 3 tries with 3 different allignment shops to get it right Also, examine the streets in your area and identify all bad spots and pot hole areas. 20’s on these M's (old and new) look great.


Modified by CakeDaddy at 12:08 PM 1/13/2009

[szh]

I currently have an 08 M35 with 18" wheels and Goodyear tires. I would like to upsize to 20" wheels. Will the ride quality suffer too much or not that bad? Thanks for your input.

We have people on here who have put 20" wheels on their car and there are pictures available.

(Please take the rest of my comments here as my personal opinions, since I am a bit biased in this particular regard. )

1. The 20" wheels will have lower sidewalls for the tires (to get the same rolling diameter so the speedo is correct, etc.), so there will definitely be some increase in road harshness. How much depends on what your tires are. You will need to be prepared to increase your tolerance level for highway bumps!

2. Your choice of available tires will be less with 20" wheels. Your current size of 245/45-18 is a very common tire size, and there are lots of brands and models to choose from. When you go to 20", the selection is less, since you have to be very careful to get the right load index for the tire. Our cars are heavy and for safety reasons, you should (actually must!) get tires with load index's of 94 to 95 (preferably even higher - when using non-Michelin tires in particular).

3. I happen to like the looks of the 18" OEM wheel on the car, and the only one I found to be equally good is the 19" Sport model OEM wheels, but only by a bit! But, then again, wheel looks are not what motivate or move me. For me, performance in braking and handling are more important - as someone once said: what stops you is not your brakes, the number of calipers, or disk size, or wheel diameters ... it is the stickiness between your tires and the road!

4. Many non-OEM wheels are likely to be not as strong as you need for the weight of the car. So, finding good quality 20" wheels is likely to be a bit expensive. Yikes!

5. The reduced sidewall of the tire for 20" wheels will also make the wheel more likely to bend or get damaged if you hit a bad bump at any decent speed. An expensive repair proposition in some cases!

Personally, I'd rather spend my money on getting the best tires I can for my existing wheels (and get the best performance I can in wet and dry weather), rather than spend money on wheels that only "look" good.

However, this issue is something that only you can best decide what is right for you!

Z

[msp]

Great info, thanks