SpeedCalc calculates vehicle speed data for cars (2 or 4 wheel drive) and motorbikes. All that is required are the gear ratios of the gearbox and final drive and the circumference of the driven tyre. All the data (A Series and Ford RWD gearboxes already loaded) you input can be saved allowing you to quickly reload details for your motorbike/car and see what effect a new wheel/tyre combination, diff ratios etc. would have
SpeedCalc is a 32 bit Windows application that will run on Win9x, NT4, Win2000 and Windows XP platforms.
SpeedCalc provides the following features given gear ratios, final drive/diff ratios and tyre data:-
For more information on how it works see the User Guide (opens in a separate browser)
Simple really and it sure beats a calculator and a sheet of paper! All I ask is that you send me back the data files Vehicle.DAT and Tyre.DAT.
For gearbox data try RT Quaife Engineering Ltd website.
Chris Cunnington Contact me
Ver 2.10 A plot option has been added to display upto 10 sets of data.
Ver 2.00 Update. After each line in the output list containing the max speed in a gear, the RPM is given that the next gear will need for that same speed. This will tell you if your ratios are to far apart and you will drop off cam or out of the powerband on selecting the next gear.
You can download either the complete program & data files or just the latest data files:-
Download SpeedCalc Ver 3.02.00 including User Guide (641 KB)
Download vehicle data file (3 KB)
Download tyre data file Ver3.xx format (3 KB)
Download tyre data file convertor V2.xx to Ver3.xx format (101 KB)
Last updated 19.04.2002