I am currently on 225/40/18 F and 255/35/18 R Toyo Proxes and about tho change them for something else, i.e either Yoko AVS Sport or S03.

I guess I will end up going for the same sizes, however I have one question regarding the difference in width Front to Rear;

I have read that the Front OEM S02 contact path is slightly smaller than regular S02's or other 205 tires, and that the Rear is slightly wider i.e. closer to that of any other 245 tire. I.e. the (nominal) difference in width is more than 40mm.

Therefore I do not quite understand why everyone seems to believe that 225/255 would be a correct combination when moving on to wider tires. I would tend to believe that this dials in more oversteer. Can of course be addressed by e.g. increasing negative camber at the rear (which seriously affects tire wear) or adding a stiffer front anti roll bar (which takes grip away from the front of the car just to maintain balance) none of these obviously ideal solutions.

Any comments?
Is the 225/255 recommendation due to restricted range of available tire sizes as long as one wants to keep roll circumference the same front and rear? Or is it because people don't seem to have noticed that the difference between a 225 and a 255 tire is actually smaller than the OEM 205/225 tire???

Qualified comments appreciated

Regards,
Simen.

 

The 225/40R18 and 255/35R18 keep the same rolling diameter as stock. Also the stagger is about the same as stock. The 205/55R16 is narrower so we go to a 225/40R18 which is wider. The 255/35R18 is also wider than the stock S02 225/50R16. So now you are wider than stock in both front and rear.
If I can help let me know.
Thank you

Jim 800-428-8355-364

 

Hi Jim,

I think you have misunderstood my post.....
Maybe I used too many words to explain something simple

OK, so here goes again:

Difference in (road contact path) width of OEM S02 205 front / 225 rear
is actually bigger than difference in width of any aftermarket 225 front / 255 rear.
(The fact that the OEM 205 is a narrow 205 and the OEM 225 is about as wide as a 245,
makes the rear contact path approx 22 percent larger than the front.)

Therefore I would tend to believe that when increasing front width to 215, the rear should be a 265, and increasing front to a 225, the rear should be a 275. But I don't see people recommend this. Instead, most seem to go with a 225/255 front to rear setup (which reduces the difference to approx 13 percent which again would make the car more prone to oversteer.)

Why is that?

(Was that clearer at all??)

Regards,
Simen.