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Sound limit issues with Kooks headers and H pipe?

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I am considering making the move to Kooks long tube headers with H pipe (no cats). I have a Corsa exhaust on my 2012 Boss 302.

For those of you with a similar setup, will I need to worry about exceeding the sound limits on track? If so, will the catted H pipe make a big enough difference?

One track I frequent has a 92dba limit. Others are 96 or higher.

Thanks
 
141
153
Exp. Type
HPDE
Exp. Level
5-10 Years
Arizona
Catless long tubes are going to turn it up a few notches. My car with an ARH catback wasn't even close to the 96db limit at one of our tracks here. I tripped the sound meter the first time at the track after I added ARH catted long tubes, x-pipe, and two bullet mufflers in the x-pipe while retaining the same ARH catback. It was marginal because it happened in the second or third session. The issue is that every Corsa catback I've heard is way louder than the ARH and you're going to be catless.

I install turndowns if I need to pass sound.
 
I added longtubes and a catted X pipe to my car last winter and gained 8-12db (!) over previous readings with the same exhaust I had before.

DaveW
 

Bill Pemberton

0ld Ford Automotive Racing Terror
8,420
8,346
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
Another reason for folks to make it to the Mustang Roundup in 2022 is there is a wonderful sign on one of the track buildings with the sound decibel limits, showing a Ghostbusters cross hatch in red across the sign!! That and new pavement make it a must for next year.

Depending on if you have the exhaust side cutouts blocked ( assume you will no longer use ) , the exhaust out the back with a solid free flow muffler/mufflers, you may be fine.
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Oh boy,,,, sound.... what a pain.. Yup, no cats, LTH and Corsas are going to put you at 98Db plus. We have a strict 90Db limit and it took a while to get it below that.

I the end the car had, a 3" custom exhaust, no cats, Dynomax mini bullets before the X pipe. another pair of longer Dynomax glass pack after, then a H pipe and finally a pair of dynomax ultraflow mufflers. All that got us 89db. And bolt on turndowns for when the air is moist.

The extra H pipe after the X pipe was a big help.
 
I appreciate the insights from you guys on this. I wonder if the catted Kooks pipes make much of a difference. Seems there’s no easy solution.
 
898
544
The catted Kooks x-pipe is quieter than no cats, but it is still very loud, especially with an aftermarket muffler. I would start with longtubes, catted x-pipe, and factory mufflers. You might also add in 3" mandrel over the axle pipes to factory mufflers. Eliminate the side exhaust.

Another option might be no cats, 3" over the axle pipes with bullet mufflers in place of the resonators, and then an aftermarket muffler in place of the factory mufflers.
 
The catted Kooks x-pipe is quieter than no cats, but it is still very loud, especially with an aftermarket muffler. I would start with longtubes, catted x-pipe, and factory mufflers. You might also add in 3" mandrel over the axle pipes to factory mufflers. Eliminate the side exhaust.

Another option might be no cats, 3" over the axle pipes with bullet mufflers in place of the resonators, and then an aftermarket muffler in place of the factory mufflers.
Thanks - I appreciate it.
 
I am considering making the move to Kooks long tube headers with H pipe (no cats). I have a Corsa exhaust on my 2012 Boss 302.

For those of you with a similar setup, will I need to worry about exceeding the sound limits on track? If so, will the catted H pipe make a big enough difference?

One track I frequent has a 92dba limit. Others are 96 or higher.

Thanks
When I had Corsa Sport axlebacks and high flow cats with an x-pipe and resonator delete, I went over 96db.

Now that I have Kooks LTHs + Kooks high flow cats + Kooks H-pipe + Resonator Delete + Corsa Sport axlebacks, it is way louder than the old setup. I am considering putting resonators on since it is so loud. Even if you have resonators with the Kooks LTH and cats and h-pipe, I don't think it will be below 96db with an aftermarket axleback. These cars are so loud with aftermarket exhausts lol.
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
This is a pic of what ended up with for two S197 track mustangs. Both of us are under 90db with out cats. The Axle back was a Dynaflow.

1636044157775.png
 
898
544
Those are mufflers in the picture above. To keep the car quite will probably require the use of factory mufflers or a combination of aftermarket mufflers installed in place of the resonators with another set of mufflers mounted in the OEM location. I would start with just the long tubes and CATs connected to the factory axle backs and mufflers. If that is quite enough, the OP can decide if he wants to try some other aftermarket combinations on the axle back portion.
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile

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