Having fitted a few of these recently. I'm very impressed with this. this is one upgrade that I think is absolutely the way to go. these boxes are now tough and reliable. and make cruising in your auto Corvette equal to that of a modern car. 4 speed with an 'overdrive' lock up torque converter. 90mph at 2500 RPM. imagine that. its what my 82 and Mums 74 does.....call for details