IDK..not gonna lie I was somewhat dissapointed, thinking i would feel a tad more quicker with the exhaust, intake, manifold but um i felt a slight increase in acceleration....sounds alot more bad ass ill post up pics and videos when their isnt thunderstorms or lightning on the island..............Now all thats left is header,dp,under drive pulley, cams yay I love spending money I dont have

 

i catback is usually just for sound. but does free up some HP but not nothing you wil really notice.

 

cat-back alone nets **** gains for power although response is definitely noticeable. get the header/dp and then revisit this subject.

 

what i mostly noticed is smoother acceleration...
and it does sound much better im sure