Sidewall vs. Tire Size

I think in real life this doesn't really matter much, but is it better to:

-get 17's with a larger sidewall that weighs a few pounds less per wheel

OR

-get 18's with a lower sidewall that weighs a few pounds more per wheel

I would say 17's, anything lighter is better. In a strictly performance standpoint, saving even the slightest bit of weight on wheels in important. Reducing the rotational mass will definitely help. However, since 18's have a shorter sidewall they may be stiffer, increasing handling performance. All in all, just going from 17 to 18 will probably not make or break a race, however 16 vs. 20? You know which will win.. Usually you start to see a performance loss at around 19 to 20 inches. It also depends on the car. A track ready STI might have 16's, whereas a track ready Miata might have 13's. If you are looking for your own car, go 18's. You will not feel any difference from 17 to 18 (except maybe in ride comfort) and 18's will definitely fit your car better. Hope this helps!

also it depends on if you are getting sort or hard sidewalls, if soft for lets say all season tires then go 18, if you get a harder sidewall tire, 17 might be the better choice

You also have to remember that 1lb unspring weight equals about 4 lbs of sprung weight so wheels and tires that are two lbs heavier per wheel are equivalent to 32lbs of extra weight on the car.

What about strictly from a handling/cornering standpoint, going from a 35 sidewall (on 18's) to a 45 sidewall (on 17's)? Would it really be a noticeable difference?

if you are going fro straight handling then go for the 17's with a stiff sidewall

How stiff your sidewall is will depend much more on the specific tire than the size. Kumho v700s with a 50 series sidewall are stiff as shit while Riken raptors with a 35 sidewall will be 50% as stiff. A lot depends on the tires designated purpose. Also a soft sidewalls effect on handling will change depending on suspension type. With double A arm front suspension your loaded wheel will naturally gain negative camber and the negative handling effects of a soft sidewall will not be as noticeable where as with a McPherson front suspension, under load you will gain 1-2 degrees of positive camber. It this situation, a soft sidewall will be extremely noticeable.

^ Makes MacPherson FWD cars feel like they're starting to oversteer when powering out on pavement, took a while to get used to when I drove a Celica.

One thing to note is that stretching a tire reduces sidewall flex and increases handling!

Josh, I assume only to an extent...

.

Lol my tires are stretched

you could do Vortex stretch

no

.

thats nothing

too much vw here. Stretched Kumho Ecstas on salad shooters = Facepalm

I posted thid through my phone

Ew all this fuckin stretch is making me sick.. stretch is a big no no!

It's a v dub thing u wouldnt understand with your family car lol! Jk jk

Hot damn Adam's the man in his family sedan.

https://www.youtube.com/watch?v=3vSe-dxlh9A&feature=youtube_gdata_player