Here is a tough question, how can you tell the gear ratios of an installed saginaw 4 speed tranny? The only means I have found is to count the rings on the input shaft which obviously can not be seen installed in car. Is there any experts that can help? Thank you very much for your help !

Jack up the rear wheels, put the trans in first gear, make a mark on the driveshaft and the engine balancer at 12:00. Turn engine over by hand and have a friend look at the driveshaft mark and tell you when it makes 1 revolution. The number of times the engine turns past 12:00 to make one revolution of the drive shaft equals your 1 gear ratio.

EX. 3 and a half turn equals a 3.5 ratio for first gear

Saginaw 4 speed
1st 2nd 3rd 4th
3.50-2.48-1.65-1.00
3.11-2.20-1.47-1.00
2.85-2.01-1.47-1.00
2.54-1.80-1.44-1.00


Hope that helps

Very clever, thanks for your help, turn clockwise the motor, right?

Here is a calculator to play with, the 'build your own' feature works for any transmission once you have the #'s to plug in...
http://www.5speedtransmissions.com/gear_calculator.html

No ring on the input is a 2.54 1 ring is a 2.85 and that is the best one. The other 2 are just waiting to explode, Both are weak, Not as weal as a T-5 but weak.

I will find out my ratio, but it must be the good one because I have hammered on the saginaw and it has never failed me yet!

When I marked dead center on motor and turned the driveshaft didnt start turning until the motors had been spun a little over a quarter turn. Do I need to start revolution counting at that point or whwn I did LT1M22 ? Thanks.