I currently drive a Cuda with a 727 and 3.23 rear end. When I get on the interstate for a shot run I am turning close to 3grand around speed limit. I am looking for something to drive like 30 miles or take a 150 mile trip.
with 3.23sand 27" tires the Zero slip number is 65=2700 rpm. Allowing 3% maximum for slip, that comes to 2800. If you are doing close to 3000 at 65, Ima thinking something is wrong. That calculates to over 11% slip.
Here is the formula;
MPH = (rpm x tire roll-out)/1056 x R1xR2
Where tire roll-out could be Diameter x 3.1416, and
R1 and R2 are your gear ratios, trans and differential.
1056 is a constant so it spits out the proper answer in mph.