I'm wondering if there is a noticable gain still with the addition of headers without freeing the catback part of the exhaust. Does anyone what kind of gains we get from just replacing cat back?
Basically, i want the extra power of the headers without the added sound of the exhaust system. Anyone have this set up?

 

I have (and many others have) the headers w/o out an after market exhaust. The exhaust is free flowing from the factory so the gains are minimal. Although I could swear the HKS gave me an added boost but I sold them because I didn't like the rumbling.

 

ya, mine is that way. Works great. All dynos from aftermarket exhaust show little gains. 1-3hp. If you want the sound go for it. Otherwise it's just a waste of $ for HP.

 

so headers and no exhaust would be a good combo, with low increase in sound?

 

Yep

 

Add a CAI for a nice higher RPM note

 

It's a tad louder but nothing of any real consequence. The intake is pretty loud above 4800 rpm

 

 

i first had headers w/ only a K&N for over a year. then i got an intake. then exhaust. the exhaust will make revveing much smoother going into vtec range.