I know short tube headers would maintain the most torque, but what would the damage be if I were to pick up some long tube headers that have 3" collectors and reduce the pipes to 2 1/2" true dual? Would I be better off sticking with the stock manifolds? The headers I may be able to pick up cheap can be seen here. And while we're on the subject, has anyone any suggestions on a non-obtrusive H-pipe? BTW, the motor is a 400sb in stock form (though not stock to the truck).