Hi, I am sure this has been talked to death already but I cannot see where. I have a 2007 A4 3.2, It came with 235 45 17 tires with 17 X 7.5 wheels. I want to change and go to 18 inch wheels to give a little more attention to the wheels. I thought 245 40 18 would work. Has anyone went to larger tires ? Any problems?

 

Nice car ! Going larger definitely works. 245's would work and possibly provide a bit better grip due to a wider contact patch but the OEM 18's come with 235/40/18's. If you plan on lowering your car, the wider 245's could end up rubbing on the inside of the fenders. FYI, 235's cost a bit less and will be lighter ... Here's a Tire diameter calculator for you: Car / SUV / Van / Light Truck Tire Calculations

Bear in mind that a larger wheel/tire combo is typically heavier and will have a negative affect on the performance of the car (handling, accelleration and ride). If you can afford it, definitely try to get a lighter wheel !! I went from OEM 18's with 235/40/18's (51 lbs) to forged 19" wheels with 235/35/19's (41 lbs) and the ride got better

What the hell, here's a pic ...

 

Thanks, wanted a larger lower profile wheel , Maybe I should stay with 17 and go with a 245 40 17 wheel instead,

 

I assume you meant a lower profile tire ... one thing to keep in mind: when you go lower profile, the wheel gap (between top of tire and fender) becomes more pronounced and then there's a desire to lower the car. Its a slippery slide down the mod bug slope ...

 

Yes meant lower profile tire. And I know about the slippery slope. The car is black and I want to install chrome wheels on it for the summer. Just want to get the best look when I do. Not a whole lot else can be done to the 3.2 , but am concidering a new exhaust but really hate to take off one so new. The wheels are easy I want winters on so new chrome for summer originals for winter

 

You could remove the 3.2 and install the 4.2 from the S4..that'd be better.

 

Yes would be, but then again lots of work to a new car. The 3.2 is really pretty peppy as it is, I just want a little more rumble to it. Maybe later in life a 4.2

 

a 235/40 tire will have a lower profile than a 245/40...