open exhaust gain?

[Bobs rare 6]

On a mid 10sec. car is there gain in opening up the dump on an ATR 2.5 exh. system? Anyone try this test? Thanks, Bob.

 

[nordy racer]

On a mid 10sec. car is there gain in opening up the dump on an ATR 2.5 exh. system? Anyone try this test? Thanks, Bob.

i haven't seen any gains in the 10's.. i have ran my best times with a closed system. Now when the car ran 12's i saw a .5 sec & 2 MPH gain with the open pipe.