Optional size 255/40/17 on 17x8 wheels
I have the Composite 19 wheels on my 98 540i.
The "optional" rear tire size for my car is 255/40/17 with 235/45/17 up front.
However, all the wheels are 17x8 in front and rear.
From '99 thru '02, the 255/40/17 tire in back was mounted on a 17x9 wheel from the factory. which were either the "brilliiant line" wheel or the M-Technic Spoke 66 wheel in the 17" size. Unfortunately, there is no 17x9 version of the composite 19 wheel that was on the '97 to '98 cars.
Question is this: is 255/40/17 too much tire for a 17x8 wheel. The service tech at the dealer said that having an 8" wide wheel makes the sidewall bow in a bit where it mounts to the wheel. He said that this bowing effect makes the tire sidewall easier to compress and could compromise the steering response of the car.
Given that, I would think that if I stayed with my existing wheels, the car might actually feel better with 235/45/17 in back. Would you all agree with that?
Otherwise, the next best choice would be to go to the M-spoke 66 wheels to have 17x9 in back.
I would really love to go to the 18" M-pars for both looks and performance, but don't feel like spending $3K+ for the wheels and tires -- and I'm not in the mood to buy some lower grade E-bay replicas.
1998 BMW 540i 6-speed (SOLD)
Jet black on tan
Dinan springs, Dinan Koni dampers, Dinan front strut tower bar, M5 rear sway bar,
Dinan Stage-1 software, Dinan clutch, Dinan short throw shifter, CDV delete, Bosch Design III injectors,
Dice I-pod kit,
Hawk ceramic brake pads....
2001 BMW M5
Silverstone on Caramel