What can a 7 1/4 rear take???

There is a formula to do this, mark your drive shaft and wheel, turn the drive shaft and count how many times the drive shaft turn to one complete rotation of your wheel.

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2 3/4 = 2.76
about 3 = 2.91
3 1/4 = 3.23
3 1/2 = 3.55

etc etc

if both wheels spin the same direction when off the ground , its a sure grip
if one wheel spins backwards its a one wheel wonder

You're talking to someone who knows little to nothing about rear ends. Even if I open up the rear end, I would not know how to figure out what gears I have unless there was a sign in there that said 2.91 lol.

Anyone want to give me a quick lesson on rear end for dummies? Or maybe refer me to a good website for this kind of information...

right there, Mike explained it