tire size

[03c5BiLL]

lookin for a little help just switched rims and tires on an 03 coupewent from stock to245/40/zr18 in frontand 285/35/zr19 in the rear want to change in cpu with predator but cant figure out what to put when they ask for new tire size in program ?????? can ahyone plsssss help me with this ty in advance BILL

[Grandpa Bear]

You can do this yourself but before doing anything, suggest you measure the rear wheel diameter of the factory stock wheel and tire vs the new set installed. Sometimes the C-6 and C-5 rubber circumfrence when inflated are the same on some but not all tires. This will solve many problems.

The Diablo sport owners manual walks you through the steps to change the speedometer when wheel sizes are changed or can be done by a speedometer shop (probably the best way) for $25.00; this way you are calibrated to the exact tire on the car.

[tblu92]

If they are asking for the diameter of the new tire size---which they probably are-- for a 285-35-19 it is 26.85"