revs per mile x 3.27 = about 3000 + at 60 mph.

so i suppose duke means 849 revolutions of the tire per mile, then after getting that number divide by 6 and multiply by 7 to get rpm at 70 then add 2 to 3% to that figure for slippage.

clear as mud?

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.