e46 M3 tire sizes

[scl18303]

I am considering replacing the stock 225/45 18 f, 255/40 18 r tires with a different size that fills in more of the wheel well. Anyone have any suggestions about going to a 235/40 18 f, 265/35 18 r tire on their M3? I know the speedo will be a little off and rotational intertia will be slightly changed from stock, but with stock tires the car doesn't fill in the fenders. Any previous experiences or suggestions would be appreciated.

2002 m3 conv

 

[frolf]

as long as you keep a fairly consistent rotational circumference your speedo won't be greatly affected. but also keep in mind rub is big issue. rotational mass isn't as big of an issue, but if you are putting on 19" spinners that weigh 40lbs a piece (god forbid) then you will have a braking distance and fade problem. ahhhh, i don' tknow the exact numbers for tire sizes on an e46 m3, but i guess thats what i know.

 

[aaron]

tire size works like this...

the first number is the width in mm's the second number is the side wall height but this time it is a percent of the tires width in mm's

so a 255/40 will work out like this...
255 *.4 = 102mm side wall height

a 265/35 will be...
265 * .35= 92.75mm side wall height.

even though the width number is larger the down sizing of side wall percent makes the second tire have a lower side wall heght. This will fill the well more in terms of how deep the tire sits in the chassis, but in terms of height from the side, it will be smaller.

play with the numbers to see what you will get.

not sure what fits, and what does not.

aaron

edit: is the car lowered (via sport springs)