I recently was given a set of G35 18'' 7-spoke wheels, but my question is will the stock tire sizes of 225/45/18 (F), and 245/45/18 (R) fit on my S14? If not, what tire sizes are suggested?

* No suspension modifications

Yeah, they'll fit just fine on a normal-ish ride height.

If you're going to try to slam it, maybe not.

Check this out.
updated-z-and-g-wheels-on-a-240sx-pictu ... 59514.html

AZ89two4Tsx wrote:Yeah, they'll fit just fine on a normal-ish ride height.

If you're going to try to slam it, maybe not.

Check this out.
updated-z-and-g-wheels-on-a-240sx-pictu ... 59514.html

Does the size of the wheels and tires raise the stock ride height of the vehicle at all?

Seeing as they're 18" wheels and S14s came stock with 16" wheels, probably a little. Maybe a few mph difference (rpm wise) depending on the tire size, rear specifically.

AZ89two4Tsx wrote:Seeing as they're 18" wheels and S14s came stock with 16" wheels, probably a little. Maybe a few mph difference (rpm wise) depending on the tire size, rear specifically.

Do you, or anyone, know what tire size on those wheels will not raise the stock height of the car?

http://www.miata.net/garage/tirecalc.html

use your stock tire size and try different width and profile combinations

215/40/18
245/35/18

i would suggest 225/40/18 maybe?