I'ld to do the speedo calculation but I'm getting a floating point error in the program.
Can somebody with the program check the result for me please?

rear wheel drive, propshaft sensor
road tyres
differential
for the moment tyres: 185-70-R14

Don't understand the input of differential ratio. The diff I use is 1-3.89 / 2-2.08 / 3-1.34 / 4-1.00 / 5-0.82

What will the result of the speedo cal and gear cal be???

Many thanks in advance!
Regards, Lennart.

Those numbers look like gear ratios rather than the final drive ratio, i think you may need to enter you differential ratio, like 3.9:1 or 3.14:1.
Steve.