hey guys my bro just put a silver top rb20 det in his TI R31, car runs good and drives great, spools up fine and no noises anywere, but when u sink ya foot into it to take it up to 3000 it takes off, good smooth power,, and then when it hits 4000 it dies out but the motor keeps driving. but its not a rough cut out, the turbo shuts down but the car is still driving, just with no turbo and it doesnt gain speed. please help!!