I just got an r200 from a 76 280. does anyone Know wat the ratio is? Or is the a way to find out?

I suppose you could count the number of rotations from the input to the output, but there is a # stamped on one of the ring gears if you can open it up.

more info here :

http://www.classiczcars.com/forums/showthread.php?s=&threadid=4270