does anyone else here hear a loud thud or bump from the back of the car when you shift hard. also what is that?

 

thats your differential trying to keep up w/ your drivetrain used to happen to me at the track when i hadnt completely mastered(still havnt) the evos timing and shift points but delay on releasing your clutch like 1/2 a second and feed it more throttle that should reduce/eliminate that noise