Originally Posted by ERinEC
My 2011 E92 has the PS2s in OEM sizes on ZCP wheels. With almost 11,000 miles on my car, the rears are practically shot.
I want to purchase the Michelin Super Sports in 275/35 and keep my front (245/35) tires on for a bit as they're not ready to be replaced. Will I have any issues to speak of with this setup? Once the front tires are ready for replacing, I would size up to 255/35.
First of all, do not mix PSS and PS2 (or any other brand for that matter), as the different grip and roll characteristics of different front and rear tyres causes an imbalance in handling. I experienced this first hand when I fitted PSS (oem size) to the rear only to see how handling changed.
Upsizing the rears only will have more effects than just increasing the tendency for understeer at the limit; you may also increase oversteer in the wet as the wider rear tyres are more prone to aquaplaning. Not only that, the car will also be raised slightly at the rear due to the increased height of the tyre sidewall, and the roll characteristic of the rear will also be changed due to an increase in rear track width. These changes will undoubtedly affect handling balance. Therefore, if you want to upsize, do it proportionally.