Originally Posted by big gear head
If you are only turning one wheel then you need to turn it twice as many times as you would if you turned both wheels together. So if you came out with 1.21 you would actually have a 2.41 gear, which was comon in the days before overdrive transmissions. Be very careful what you watch on youtube. There is a lot of completely wrong stuff on there, especially when it comes to rear ends. The Camaro rear ends have the code stamped into the right axle tube on the front side.
Big Gear is exactly right here. If you had a limited slip rear end with both wheels turning then you could turn it once. but with one wheel stationary and one wheel turning the spider gears in the differential will transfer the power in such a way that you must turn the wheel twice.