Fill in the fields that you know and check the button corresponding to the value you want to solve for. For now, it's necessary to tell the program what to solve for. After I screw around with it for a while, I'll be able to get rid of that requirement. It's just a quick hack at the moment...

Speed (MPH) RPM Tire Diameter (inches) Rearend Ratio (inches)

Speed (MPH)
RPMs
Tire Diameter in inches
Rear gear ratio (eg, enter 3.73 if you've got a 3.73:1 rearend
Transmission Ratio   Powerglide (small block) Powerglide (big block) TH350 TH400 TH700-R4 TH200-4R M20 M21/M22 Super T10(a) Super T10(b) Super T10(c) Super T10(d) Richmond 4+1 Richmond 6-speed(a) Richmond 6-speed(b) Borg-Warner T56 (a) Borg-Warner T56 (b) Borg-Warner T56 (c) Borg-Warner T5 (GM Close Ratio) Borg-Warner T5 (GM Other)
enter a value if known, or choose your transmission from the list (choosing from the list assumes final-drive gear. If you want to know results for a gear other than the final gear, get the ratio from my transmission list)

Credit must go to the wonderful folks at Petersen Publishing - esp.. those at Hot Rod for the Dec. 97 issue - for providing the formula I use here. I've also gotta give credit to the people at Summit Racing for the Tranny Ratio list. Also, Salfdez@aol.com contributed ratio T56(c) based on a '93 camaro's tranny.