Rough Acceleration and Deceleration problem???!?!?!?

[deathBooster]

I am pretty much done with the SR swap on my car.. Everything is fine except for the drastic change in idle when accelerating and decelerating...

The problem starts when i hit the gas and then let go.. the engine revs a little and pusshes me forward like if i where downshifting or engine brake... it makes the ride really uncomfortable..

then when i accelerate it pushes me backward.. it acccelerates too hard.. there is no way to control or avoid this...

Anyone have any idea of what could it be???