love4theluv wrote:
im looking for something a little bigger to lower my rpm at highway speed
changing tire size will not change the rpms as much as you think. not only that, but the bigger the tire, the more weight you have, the more the engine will have to work to turn those tires. keep that in mind.
use this site to figure out what would be the best size. you might also consider changing wheels to 15 inch since they also allow for more variety of tire sizes.
http://www.miata.net/garage/tirecalc.htmlthe closest metric size to the factory tire will be a 195/75-14. I changed to a 225/70-14 and while it drops my tire rpm's by about 26 turns, it's not enough to make a HUGE difference.
changing to a 215/75-15 will definitely make a difference, but you will run into trouble when installing the front and finding that you can't turn the wheels all that well up front.
personally, i recommend the 225/70-14's. it's what i run and they are relatively cheap. (try discount tire. i buy all my stuff from them)
_________________

To the Oquirr hills for awesome thrills! Go-go 4wd, Activate!