Need advice on 18s

[Pimpin_29y]

18x7.5 +45
245/45R18

Will this be ok for m3 sedan w/gfx?

[bubba1983]

i think 245 tires are too big

[Pimpin_29y]

Thanks bubba:)

[chaser]

245/45/18 is about 1.5\" longer than stock\'s diameter. I\'ll offset the speedometer :(

[chimp]

check this link out it should help you out:
http://www.miata.net/garage/tirecalc.html

i beleive a 215/45/18 would work or a 225/40/18 would work. i know i have the 40 series on my 18\'s with no problems at all. but check that tire calculator out since it is a very effective guide to conquer the task of getting the proper tire size.