What does chevy mean by Locking rr. Differential? Is this posi? Because I paid $410CAD for this option and I can leave one hell of patch, but with only one tire. Whats locking then?

Also I plan on getting a magnacharger supercharger. Should I go with 4.10 gears or keep my 3.73 and get a stall.

 

Its a locking rear differential. (G80 option) Its not all that great since it tends to breaks with a high torque motor and it also doesn't lock after 20 mph. A limited slip differential like an Eaton Link would work better than the stock unit. Those 3.73s should work great with the Magnacharger.