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Tire diameter redux - ABS and RPM

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Old Jun 17, 2011 | 02:40 PM
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Tire diameter redux - ABS and RPM
Just purchased a set of Nitto NT01s (235/45/18 & 315/30/18) for DE days on my C4S. While looking for temp recommendations I've found numerous threads on different sites talking about ABS concerns and tire diameter. Unfortunately there doesn't seem to be an authoritative answer beyond 4% variance, though a concering aspect was a discussion of wheel RPM deltas i.e. fronts must turn faster than rears. With these sizes, rears turn 1 RPM more than fronts - am I about to be an unhappy camper?
 
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Old Jun 17, 2011 | 03:19 PM
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I just read a post somewhere about this. As I remember the OP did not have any issues.

I've always tried to stay within the 4% rule for front/rear.
 
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Old Jun 17, 2011 | 03:40 PM
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Yup - it's within the 4% but it's damned closed at .965. It's the OD and RPM differential that caught my attention: OEM F/R, rear is 29 RPM slower.
 
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