Different tire diameter, does it matter?

[spongebob]

Just found a set of really cheap Bridgestone SO3, which I think some people here has given great feedback.
Sizes where not 100% correct though.
Rear 255/40/17 ( original size)
Front 215/45/17( smaller than current 205/50/17)
I suspect that the front tires will rotate at higher speed than the rear but will this mess anything with ABS or speedometer?

[thstone]

In a perfect world, yes the front tire rotation will not be matched to the rears. In the real world, its probably not enough to make a difference.

Some owners like to keep their cars "spec on" and others are willing to compromise a bit if its not going to create problems. Depends where you come in.

[Johnny Danger]

Originally Posted by spongebob

Just found a set of really cheap Bridgestone SO3, which I think some people here has given great feedback.
Sizes where not 100% correct though.
Rear 255/40/17 ( original size)
Front 215/45/17( smaller than current 205/50/17)
I suspect that the front tires will rotate at higher speed than the rear but will this mess anything with ABS or speedometer?

Actually, given the lower aspect ratio (sidewall profile), the overall circumference will be fairly close . Certainly not enough to effect the the ABS or speedometer that much .



Stock Tire - 205/50R17 Search Tires Tire 1 - 215/45R17 Search Tires
Section Width: 8.07 in 205 mm
Section Width: 8.46 in 215 mm
Rim Diameter: 17 in 431.8 mm
Rim Diameter: 17 in 431.8 mm
Rim Width Range: 5.5 - 7.5 in
Rim Width Range: 7 - 8 in
Overall Diameter: 25.07 in 636.77 mm
Overall Diameter: 24.61 in 625.09 mm
Sidewall Height: 4.03 in 102.36 mm
Sidewall Height: 3.80 in 96.52 mm
Radius: 12.53 in 318.26 mm
Radius: 12.30 in 312.42 mm
Circumference: 78.75 in 2000.2 mm
Circumference: 77.31 in 1963.6 mm
Revs per Mile: 829.6
Revs per Mile: 845.1
Actual Speed: 60 mph 100 km/h
Speedometer1: 61.1 mph 101. km/h
Speedometer Difference: - Speedometer Difference: 1.868% too fast
Diameter Difference: - Diameter Difference: 1.84%

[BYprodriver]

You shouldn't have any problems with that size & you may like it better!