Unconventional Tire Size Combination

[sr71bb]

First my car has BMR loweing springs on it with some other BMR handling goodies. This car is a daily driver but I have raced it in the TEXAS mile and have started to do some autocrossing with it.

I LIKE a slightly raked look where the rearend is slightly higher than the front. I also like the same amount of space above the top of the tire and the CENTER of the wheelwheel.

For a daily driverr, my opinion is that you need AT LEAST 4 inches of ground clearance.

Taking all this under consideration, I now have the following tire combinations and they are mounted on VOSSEN wheels

Front: 255/35-20 Nitto Invo (27 in. OD, stock is 28.7)
Rear: 295/35-20 Nitto Invo (28.1 in. OD stock is 28.7)

This results in ROUGHLY 5 inches of ground clearance under the front nose of the car, 4 inches ground clearance just in BACK of the front tires and 5 inches of ground clearance just in FRONT of the rear tires.

There is approximately 1.5 inches of space above ALL of the tires and the centerpoint of the wheel opening.

I know the theory here is that the OD of the front and rear tire wheel combinations should be within a half inch or so or each other but so far I have not seen any negative effects,

I do like the cosmetic effect of the tire size changes and I will post back more info regarding any handling chracteristic changes.

The slight nose drop should be slightly more efficient in Texas Mile racing and I am not sure yet the effect on autocrossing but I an off to the alignment shop tom.

[SUX2BU]

Originally Posted by sr71bb

I know the theory here is that the OD of the front and rear tire wheel combinations should be within a half inch or so or each other but so far I have not seen any negative effects,

I don't know who pulled the 1/2" figure out of their ass, but it is not correct. You have to have a 6% difference in wheel speed to cause problems. At 28.1" 6% is 1.686". So you would have to run a 26.414" front tire with the 28.1" rear to have any problems.