Found a very useful graph of tire radius vs inflation pressure for anyone interested in correction factors for tires.

Like me... I just went from the stock size/pressure of 175 65 14 @42psi to 185 65 14 @ 51 psi. I found the revs per mile but not with pressure compensation.

http://ecomodder.com/imgs/chart-tire...n-pressure.jpg

1.5mm change in RR between 35 and 50 psi that works out to:
1737.99mm Dia @ 35
1747.41mm Dia @ 50
difference is .5% rolling diameter. meh.

Original tires Bridgestone RE92 175 65 14 xl: 902 rev/mile
New tires: Nokian WR g2 185 65 14 xl: 884 rev/mile

2% correction for tire size and .5% for pressure= 2.5% total correction.