99 323i - Max Tire and Wheel Size

[brianholden]

Hi all, Need some help. I have a 1999 323i. It currently has puny 15" alloy wheels (one step above hubcaps) on it. I also own a set of M3 18" OEM Wheels & Tires. This new size is FRONT: 225/45ZR18 REAR: 255/40ZR18. The rim sizes ae FRONT: 18x8 REAR: 18x9. My question is simply...will these new wheels and tires fit on this car? They obviously fit when the car is sitting still, but I am concerned about high cornering or suspension hits. Will these tires/wheels ever rub? The owners manual says the follow are approved sizes. REAR: 255/35ZR18 - 18x8.5J (What does the J mean?) and REAR: 225/40ZR18 - 18x8.5J.

Thanks for your help in advance.

Just need some answers or a better place to ask this question.

BIMZONLY.