5* of knock retard at WOT please help

[dsmuts]

Headers are hands down the best mod I did to my car. It helped out tremendously. Knocked 4 seconds off my 0-100 times.

[blueguy]

Kind of a dead thread but im experiencing the same thing almost but im running on a stock pulley with sd headers and 3 in exhaust. Engine only has bout 2500 miles on it. i still need to put a new fuel filter on it but i dont know if that would help any. The car has just seemed kinda sluggish and my throttle response isnt the greatest. just doesnt seem like im making the power i should be but im not sure if im just expecting to much. I know i need a tune but just didnt know if anyone would have any suggestions on other things i should try? i do know i have a tiny exhaust leak to on my crossover for my headers but that should be getting fixed tomorrow

An exhaust leak before the o2 will destroy fuel trims...

could be running pretty rich, that would explain sluggishness...intake has nothing to do with that.

Fix that, check the motor mounts...see if they are toast.