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      02-26-2015, 03:15 PM   #77
Boss330
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Quote:
Originally Posted by gmd2003 View Post
The wheel/ tire can have the same speed and different rpm's yes , but is the dyno measuring the speed or drum rotations.At any rate good gains with the tune , I hope to see one at the strip soon for real numbers !
I'm pretty sure the dyno reads the drum/roller rpm and then calculates speed based on the drum diameter.

Tangential speed of the drum = tangential speed of the tire = theoretical speed of the car (since there allways is a degree of slip between tire and road/drum, - tangential speed of the drum/tire won't equal vehicle speed 100%, more like 99,99%)
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