17's or 18's???????????????

[StewRat]

how does this metric tire size work? I understand the first is the circumference, but the second number is where i get lost. I think its the diameter of the side wall, but which is taller, 40 or 45?

[hi-power WRX]

+18

[WRXKidid775]

first number is the width iirc, second number is the profile of the sidewall. bigger number = bigger sidewall. the last number explains itself.

[nicolas316]

i have 18'' prodrive pff-7 225/40, i dont know the difference ### i have them since i got my car, but the roads here are either highways, or upwards with alot of turns, would 17''s be more efficient for these roads??

[BlueBomber]

with 18s do you have to worry about fenderwall rub with lowering springs?

[mosc]

Originally Posted by BlueBomber

with 18s do you have to worry about fenderwall rub with lowering springs?

the height of the rim has little to do with the actual dimensions of the tire. Check out the Tire/Wheel faq I'm writing:

Wheel / Tire FAQ

[BlueBomber]

yeah i read that it helped me understand alot thanks again =D

[mosc]

Yay!