I'll add this info to Vinnies post some of the readers may like to have these!~
= = equals
x = multiply by
/ = divided by
overall tire diameter = mph x axle ratio x 336 / rpm
rpm = mph x axle ratio x 336 / tire diameter
mph = rpm x tire diameter / axle ratio x 336
axle ratio = rpm x tire diameter / mph x 336
These track formulas are so easy I've used them for years at the track they are designed for calculating with a final trans ratio of 1 to 1!
If your getting mph a little low on a pass calculate the tire diameter you need to do the mph your looking for! If your running out of gear calculate, if your pass is bellow rpm and your not at the top of your final gear calculate!
A lot of the tables on the web have rounded off factors and errors its so easy these days with calculators to do math and algebra why look at the internet! copy these and laminate them keep em safe! Ill bet all the old guys on here have these and more and calculate with them and then someone looks on the web gets a graph or quotes a table and insults fly! Like dcr and scr tables!!!
At least use the formulas to check the internet tables to see if the table is correct and then you know its right when you quote it!!
Some one is going to ask " what about overdrive "
These are track formulas! Or road formulas for 1To1 overdrive is to save fuel your rpm will drop a little in final drive ( expected)