Originally Posted by NCEC
This is not the first time I look at your setup, i love how classy it looks with those Alpina! I can't help myself to get a set of those for my F10. I know the recommend tire size is 245/35 and 285/30. Do you know if it can go 255/30 and 295/25? Or any other size? Want to give a bit more meat to protect the rims! It took me almost two months to find the set and ship all the way from US to Hong Kong
Actually, the combination you mention give you less "meat" than the one I suggested. The height of the lip of the tire relates to the numbers you ported. The second number is the percentage of the first number that results in the height of the tire. As an example a 245(mm)/35(%) tire results in a lip height of 85.75mm. The one you propose, a 255(mm)/30(%) results in a lip height of 76.5mm. The taller the height, the more protection you have in the wheel and the better ride you get. Performace is better with a lower lip but there is apoint where the lower ratios give you worse performance. I think at this point we are passed the ideal lip height for performance. I don't think there is many racing cars, if any, that run 25 section tires.
I hope that helps.