Does anyone know (roughly) the shift points in MPH for a TR that shifts at 5500 RPM with stock rear end and 28 inch Street ET's.
Well, an approximate formula would be:
MPH = (TD * RPM)/(TR * GR * 336)
Where:
MPH is the miles per hour
TD is Tire Diameter in inches
RPM is Revs Per Minute
TR = transmission gear ratio
GR = rear end gear ratio
1st gear is 2.74:1
2nd gear is 1.57:1
3rd gear is 1:1
4th gear is 0.67:1
So, for:
28" tall tires and 5500 RPM shift points ...
1->2 we get ~48.9 MPH
2->3 we get ~85.4 MPH
3->4 we get ~134.0 MPH
and for grins it's ~ 200 MPH in 4th
Of course, that assumes perfect efficiency, no air resistance, yada yada
I'd guess that the shifts are significantly under those numbers (from memory).
Thank you, Ken. We're setting a friends GN up for the 1/8 mile. He's running 98 MPH in the 1/8 and we were hoping to avoid that 2nd to 3rd shift. guess not.