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I have calculated the drag and rolling resistance in Newtons. I have the wheel radius, torque and RPM curves, the car's mass, the transmission gear and the differential/final drive gear ratios. The car is FWD. For simplicity, assume there is 1 gear ratio with a fixed rpm & torque output.

*F = ma*, naturally.

Here says we can get velocity using RPM

https://en.wikipedia.org/wiki/Gear_train#Example_2

v = [(wheel rad * 2 * pi) * engine rpm]/(trans gear * drive gear)

And looking at equations from here

http://www.engineeringtoolbox.com/cars-power-torque-d_1784.html

Force = [(Torque * gear ratio) * (Engine RPM / gear ratio) * efficency value]/(wheel radius * wheel RPM)

which does actually give a reasonable value except gear ratio has no impact and it tries to divide by zero if the car is still.