Bought rearend, how to check if it really is 3.42?

[raxxus]

I bought a 97 rearend from a lt1 camaro, with 3.42's and posi ( I know the posi works [img]graemlins/evilgrin.gif[/img] ). But how do I check to see if it really came with 3.42's? I heard you should spin your driveshaft, and for every 3.5(around that) revolutions it makes, the wheels should spin once or something? Thanks guys!

[chazz]

take the diff cover off and count the teeth on the ring gear and the pinion gear, then divide the two numbers. examp. ring gear count 41,pinion gear count 12, 41 divided by 12= 3.4166666 IE 3.42:1