Demon's Camaro

I have a built tranny out of a 95 in my car right now and when I put the car into drive it SLAMS into drive, literally bucking the whole car. Also when under acceleration the car jolts again it appears in the middle of first gear. When under hard acceleration it appears to be less of a jolt. Also have a 2400 rpm stall installed right now. Car has 2.73 gears.

Heres the trannys specs: The tranny was built with race
frictions and steels, the beast reaction shell, a 29
element input sprag, a 10 vane pump, hi performance
kevlar band, an elevated pressure regulator spring, and a
transgo HD2-C reprogamming kit

As to what that all means I have no clue, but I bought it from a reputable board member and it was to replace my blown tranny.