SpeedCalc - how fast does it really go?  

Downloads

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:-

• Vehicle speed/1000 RPM
• Maximum overall speed in top gear
• Maximum speed for each gear
• The RPM drop between gears and the RPM the next gear is engage at
• Engine speed at a set range of speeds e.g. 30, 40, 50 & 70 MPH
• Speed output in either MPH or KPH
• Calibrate a trip meter without having to drive a measured mile

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 3.02.00

• Bug fix in printing of performance graph. Now prints to laser and black & white printers.

Ver 3.01.01

• The performance graph can now be saved as a JPEG or bitmap file.

Ver 3.01

• Performance data text can now be copied to the clipboard.
• The performance graph can be copied to the clipboard or saved as a bitmap file.

Ver 3.00

• New GUI layout, hopefully a lot easier to use!
• Performance data can now be calculated in KPH as well as MPH.
• Internal rounding errors fixed in algorithms.
• User Guide added for basic help.
• AND THIS IS IMPORTANT: The tyre data is now input as the tyre circumference and NOT rolling radius. This is easier to measure and more accurate. But it does mean that any version 2.xx data files won't work. I've created a conversion program you can download to the directory where your Tyre.DAT file is stored, just run it ONCE and your file will be converted.

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