So I've had the 3" catless helix exhaust on my car for about 2 years now. since i had a little curb incident, i got a chance of swapping it out for something different. instead of sticking with helix again, i ordered a hks hi power catback and kept the dp/up pipe from helix. the first thing i noticed, was the the hks has a cat in the midpipe. i thought to myself this would be a good thing since i got tired of the loud rumble. my first impressions of driving it were amazingly different. it is probably 1/2 as quiet as the helix exhaust. i can actually talk to people in the car without raising my voice, lol...and the highway drone is non existent. i can feel the top end has taken a hit in power, but its not that big of a deal. everything feels smoother and more steady than with the helix. no pops, bangs, and bogging as much. and i think my neighbors will like me more :)

bottom line...if you want the fart can look without the noise, hks is great.

yea I loved my HKS high power. Very good rumble and a extremly popular catback. I want to try the invidia N1 race catback or the new titanium helix cat back.

the first thing i noticed, was the the hks has a cat in the midpipe.

That isn't a Catalytic Converter, it is a Resonator.

i thought to myself this would be a good thing since i got tired of the loud rumble.

Thats what a resonator does, it cuts down on the droning, some of the noise, and can change the tone of the exhaust note. You can think of it a second mini hiflow muffler in the middle of the exhaust.

my bad...it is a resonator. and it does wonders!

after a while, the helix got a little loud and annoying for daily driving. even though it had one of the nicest rumbles, the droning just killed it and my ears. the 2 tones on the exhausts are totally different. helix is a deep rumble, while the hks is a quieter purr...nice for a change.

the only thing i noticed was the the rear section comes very close to my cusco rear sway bar. once in a while i'll hear it rub, not sure if its a big deal or if anyone else has the problem...

The Kartboy extended exhaust hangers should fix that problem.

Just out of curiosity, which DP are you using? I'm looking for feasible DP/CBE combos for my 02 sedan that require little or preferrably no fabrication. And I've heard good things about the Hi-Power and the Carbon-Ti as well, so those are def. on my list of potential CBEs

the hks hipower exhaust is by no means quiet, the helix is just real f***ing loud :lol:

but give it some time, the hipower is a pretty loud exhaust and it'll only get louder as you break it in.