Greyhaven7

wouldn't that screw with your quattro? Confuse it? or at least wear the tires faster?

meem

225*.40 ~= 255*.35

dannyTTnyc

have fun with tire sizes<ul><li><a href="http://www.miata.net/garage/tirecalc.html">tire calculator</a></li></ul>

meem

the difference is in the noise.

dannyTTnyc

and how they effect the speedometer.

they are about the same, i was surprised that tio wass actually closer



Now noise, ride, and handling are a different story

gliTTch

Just be glad it wasnt worst man and your cool. Best of luck with the new parts...its gonna look soo SICK!
-Krit

Greyhaven7

225-40-18

225= width of tire in milimeters
40= percent of width that sidewall is
18= diameter rim it fits on

(remember that we're tlaking about diameter, so you have to multiply by 2 since you cross the sidewall twice in the rolling diameter.)

SO.. the 35's sidewalls are 78.75mm
and. the 40's sidewalls are 90mm

a difference of 11.25mm

times 2 (two sidewalls in diameter)= 22.5mm or 2.5cm difference.

Greyhaven7

huh? my tires are 225-40-18 and they're stock....

Greyhaven7

formula for circum. of a circle (tire)
pi*d (d is diameter)

18inches is about 457.2mm
that plus the sidewalls times 2 should give us the diameter of the tire+rim

40=637.2
35=614.7

circumfrance of tires=
40=2001.7mm
35=1931mm

difference of 70.7mm or 2.7in

which means every time the tires go around, your rear tires have gone 2.7in further than the front ones.

front tires make 812 rotations per mile
rear tires make 838 rotations per mile

rear tires have to turn 26 more times per mile than the front tires... THIS CAN'T BE GOOD!!!!!

meem

you've misread. 2*5*5 / 35, not 2*2*5 / 35