Straight Pipe + 3 resonators, too much ?
 

Im currently running a Stock header + catless FP, 2 resonators on a muffler delete and no resonator on the Center Pipe, also have tuned it with Dastek Unichip.

Although it sounds pretty good, i think going catless header will give much more power. Basicly a Straight Pipe with 2 resonators behind the Exhaust Tip or maybe add 1 more resonator on Center Pipe. I dont doubt the power gains, but im concerned about the rasp / rice sound. Any suggestions ?

Well, if it's too loud, Bubba says you can always add a couple of mufflers - :D

humfrz for Bubba

These cars get really loud without Cats!

My experience, Stock exhaust with no cats louder than AVO turbo kit with muffler delete. I would do it but you will probably want to look into putting a muffler back on. Unless you just want to be stupid loud.

I have the stock midpipe, double resonated FP and test pipe with a resonator along with catless header. The car is pretty damn loud even with all these in place and its a track only car (hardly sees the street but when I do drive to and from the track, it gets fairly annoying). But then I dont have anything in the rear (rollbar back everhing is removed including the seats) Everyone has their own yardstick but if it were my street car, I would put a muffled rear end as this thing drones heavy.

Lutfy

I DD Tomei UEL, OP, HKS FP, and 60R. 3 resonators... Anything over 15% throttle is "look out for cops" territory. Knock on wood, no tickets and have been running this setup for over a year or so. Below 3k rpm, it sounds great. WOT, sounds great. In the middle, less than ideal.

I DD ACE header, hks double res FP, and CSG touring86 catback. By no means would I consider it loud or ricey. It’s a little louder then stock. Just enough to know it’s there, but not enough to be overly abnoxious. And when I get on it full throttle it’s got a good crisp deeper tone. But still not stupid loud.

I had the same set up that you're considering, catless UEL & catless FP + aftermarket OP/Catback with one resonator and two mufflers. It was LOUD.

Switched my Tomei UEL back to stock because it was too loud for me. However, it did sound AMAZING (IMO) and the torque dip completely disappears when paired with a tune + full bolt ons.

I'm also from the catless w/ stock catback crowd. It's still loud. Resonators, for clarity, help smooth out rasp / vibration in the exhaust, they don't work as much to reduce overall volume. Get a muffler and that'll be the best you can do.

I was originally like you. First mod was a ace header. Wasn’t crazy loud, but the exhaust note was just “off” to me. Then got a hks double res FP, cleaned up the tone a little but getting rid of second cat also made it a bit louder. Still not crazy. But I still didn’t enjoy the exhaust note. Then finally adding the CSG touring86 actually made it sound quieter. Partially bcs it might be quieter. But also it’s a little deeper lower tone and overall sounds a lot cleaner and enjoyable to hear, which could also add in the perception of being quieter then stock catback.

And yes to piggyback off what you said. Cats and mufflers can dampen or reduce the volume. Resonators can change the tone and cancel out certain frequencies to reduce or eliminate drone, rasp, or vibrations for a cleaner better sounding exhaust tone.

I guess i should keep my current setup since it seem like going catless header is just too loud, but still tho, does it really makes a huge difference performance-wise ? i've read so many posts say it does, but my tuner said the otherwise.

I got more than 10% HP gains and better torque curve from tuning with current setup, how much more can i get if i go catless header and re-tune it ? if its just 3-5 more whp i dont think it worths losing the exhaust note i already like

Just a note from the exhaust sticky:

Catless header with tune (petrol) around 20 wheel hp
Catless header with tune (E85 fuel) around 30 wheel hp
Catted header with tune (petrol) about 15 wheel hp
Tune will take full advantage of your header
Tune will disable the P0420 cel code - no need for spacers or de-foulers
Tune will further smooth out torque dip
Smoother running, smoother idle

You could try a high flow cat and or a high flow cat in the FP.
A cat in the header is the biggest exhaust restriction. A lot of threads people just decatting stock header with a tune and getting decent results. But the biggest NA hp bump you can get is a quality catless header with a tune.

If all you have is a stock header, with catless front pipe, catback exhaust and a good maf scaled cai with custom tune. I would expect a quality catless header to double your gains. Really a necessity to any substantial NA performance increases.

Also you mention muffler delete? A good muffler should substantially reduce volume with out being any restriction. Maybe look at a JDL ultra quiet FP and a CSG Touring86 catback. That should not be a restriction and be very quiet. Even with catless header.