Full Kooks headers and green cat back system not as loud as I thought it would be 16 gt350

[DeathvalleySC]

Hey guys, I’m new to the forums. I apologize if this has been brought up. I recently installed the full kooks headers and green cat back system with axle back exhaust. It’s not as loud as I thought it was going to be. It has a really good deep sound but it’s not as loud as I would’ve hoped. Will it get louder over time? I’ve been doing research on the topic and everyone that’s installed the kooks systems have kept the factory mufflers to keep the active exhaust option. No one has complained about them being to quiet. I was hoping to get some feedback from others that have installed the full or partial kooks systems on the gt350.


Sent from my iPhone using the svtperformance.com mobile app

 

[jvandy50]

It’s the axle back/mufflers making the big difference.

Of course, many complain that headers/res delete with stock mufflers is too loud....especially catless.

The kooks mufflers have a great sound, but lack in the volume department

 

[DeathvalleySC]

I’ve also read the kooks axle back is about a 10 hp increase from the factory mufflers. I guess I need to figure out if I want the power increase or lack of loudness. I’m still wondering if they will get louder over time. I’ve read that they get louder after 500-1000 Miles. I’m at about 100. Lol


Sent from my iPhone using svtperformance.com

 

[jvandy50]

I would give it some time for sure. After that i bet if ya still want louder you can swap em back out for the factory mufflers and sell the axle back to someone looking to quiet their’s down a bit.

 

[ANGREY]

Hmmmm, I'm wondering how much the cats are muffling the exhaust.

Judging from vids online, it seems to scream pretty well to me.

I have a full ARH system and it seems quieter at idle and low RPMs than even the stock quiet mode, but under WOT and higher RPM it sounds like a hayabusa on steroids after he found his wife cheating and she left the parking brake on.

Does the Kooks system allow you to swap out the cats for a straight pipe section? Is it segmented at the cats with connectors?

 

[DeathvalleySC]

Yes, I can change out each section. There’s actually an off road xpipe that kooks offers with no cats. That’s another option I have. I’m going to give it a month or so. If it doesn’t get louder try to put my factory mufflers back on. I bought my 2016 used with low miles. The guy that owned it before me did some modifications. Some were good. Some not so much. One issue I have with what he did was he put kooks headers on the car and cut the flanges on the end of them and welded flat flanges. He then welded in cats with no rear oxygen sensors. The xpipe section looked crazy with all the welds. He kept stock mufflers. It sounded great but from the vibrations the car puts off one of the cats broke off inside and caused a bad rattle. This was due to the flat flanges not having any play in them. He also took off the vibration dampener weights (which I can’t find replacements to order). So I decided to replace the whole system headers and all. I actually have a set of kooks headers that I’m going to sale but they have flat flanges welded on them. The flanges could be taken off and correct flanges welded back on.


Sent from my iPhone using svtperformance.com

 

[Ninjak]

I run the Kooks Headers with the O/R Kooks pipe. I also run the OEM Ford out back. Car sounds great and at WOT you know I'm coming

Honestly I been told my car sounds really good. I am pretty happy with the setup.