Open headers vrs. full exhaust

tubbedamx said
I've had the opposite experience. When I take the exhaust off my amx I have to jet up 4 sizes to reap the benefits of .15 in the quarter.

The exhaust on my amx is 3 1/2inch to an xpipe then out with 3inch.

Are you dropping the exhaust at the track??...you'd deffinately see a gain if jetted correctly..but he's talking about through the dumps...