[decooney]

Hey Art,
if you can, try moving the driveshaft, not the wheel, and count it again just to make sure there is not any slip going on. I'm about about 3200rpms with 26.5 inch tall tires at 60mph with a 3:31 rear. If the rear came from ERA, I was thinking maybe its a 3.54. My friends Cobra with 3.54 revs 3500 at 60; with 25.7" tall rear tires. If you have shorter rear tires, that would definitely make it rev a bit more too...but would not skew your previous count figure of 4.1 rotations; if there was no slipping going on. Sorry, I was just stuck wondering why someone would put 4.11s in there for a 2550lb car, with a 428. IMHO, you would be much happier with 3.31 ratio if you truly have something lower than 3.54 and especially if you have 4.11s. Good luck.