Quiet exhaust option for supercharger

[funkynsx]

We've got tight noise control laws here in Melbourne Australia and i need to find a quiter exhaust.
I currently running a SOS supercharger with SOS endura lite exhaust, prospeed 100 cell high flow cats and DC headers and will be running @11psi.

I also have a ARC titianium race exhaust but its probably not much quiter than the endura lite.

Can anyone suggest a quieter option than the exhausts i have?
I heard the comptech exhaust is quiet but can it handle a boosted engine?

I'm going to change back to oem cats aswell for less noise and emissions.

Any help would be appreciated.
Cheers

 

[N-Wing]

I will be interested to see what you come up with. I was going to get an endura lite to approximately match my ARC Ti Street due to damage. I thought the endura lite was pretty quiet. You could try silencers to cut the noise back. I wish we could flip a switch and turn them off like the 360 Ferrrari.

This is the only gauge I know of and the link is not on all their exhausts for some reason:

http://www.scienceofspeed.com/sos_resource/FAQs/NSX/eap/exhaust_comparison/default.asp

 

[funkynsx]

I will be interested to see what you come up with. I was going to get an endura lite to approximately match my ARC Ti Street due to damage. I thought the endura lite was pretty quiet. You could try silencers to cut the noise back. I wish we could flip a switch and turn them off like the 360 Ferrrari.

This is the only gauge I know of and the link is not on all their exhausts for some reason:

http://www.scienceofspeed.com/sos_resource/FAQs/NSX/eap/exhaust_comparison/default.asp

I dont want to turn you off the sos endura lite exhaust.
Chris told me its similar to the arc ti street in volume.
I just need my car to be quiet.

Anyone run the CT Engineering gen 2 exhaust with a supercharger?C would be quiet enough T Engineering Gen II Exhaust

 

[ozone]

I dont want to turn you off the sos endura lite exhaust.
Chris told me its similar to the arc ti street in volume.
I just need my car to be quiet.

Anyone run the CT Engineering gen 2 exhaust with a supercharger?C would be quiet enough T Engineering Gen II Exhaust

I have CT exhaust. I bought it new last year so I am not sure if its gen1 or gen2. It works perfectly with SC and is plenty quiet. When I was buying I was looking for good performance and quiet and this fits the bill.

Now I kind of wish I went with a louder exhaust but other than that, no complaints.

 

[goldNSX]

What noise test does your car have to sustain?

 

[funkynsx]

There's only a test if you get cited by the police.
I think is around 94-96 db.
As long as i'm around under 100 db i should be ok.

I heard the early comptech exhaust had issues with FI.

Does anyone know if has been resolved in the gen 2 exhaust?

 

[goldNSX]

We've three different way of tests
1. a drive by test, measured at 7.5 meters
2. a stand still test, measured at 3/4 max rpm at 7 meters
3. a stand still test, measured at 3/4 max rpm and 45 degrees/1 m way from the exhaust tip
The last one is the loudest.

Things to calm the car down (in this order):
- exhaust (most effective)
- cats
- headers
- intake snorcel (AIS?)
- OEM engine cover (factory dampening)

A db-meter of cat.2 is quite affordable and precise enough to show were you now are and what test you have to do.

 

[nsxnut]

I suspect the stock cats will quite it down a bit.
A stock exhaust will be quieter but will have to much back pressure for a car with 11lbs of boost.

I have a custom made exhaust I use at Laguna Seca. It will pass the 92db sound restriction.
It is made out of a comptech exhaust that was enlarged "2x" and repacked.
It is huge and is a tight fit under the car but really quiets is down.

It is not for sale.

Later,
Don

 

[funkynsx]

I suspect the stock cats will quite it down a bit.
A stock exhaust will be quieter but will have to much back pressure for a car with 11lbs of boost.

I have a custom made exhaust I use at Laguna Seca. It will pass the 92db sound restriction.
It is made out of a comptech exhaust that was enlarged "2x" and repacked.
It is huge and is a tight fit under the car but really quiets is down.

It is not for sale.

Later,
Don

Thanks Don,
I dont want to run the stock exhaust.
I want to run the CT gen II exhaust but i need to know would this stand up to 11psi boost?

 

[nsxnut]

Thanks Don,
I dont want to run the stock exhaust.
I want to run the CT gen II exhaust but i need to know would this stand up to 11psi boost?

When I had the Comptech exaust I eventually burned it up. I believe this was a gen I.
This was with and original CT supercharger with the 9Lb kit.

I now have a bigger blower and Low compression 3.2 motor. I have the SOS Endura light exhaust and I really like it. :smile:
I can't pass sound at Laguna with that exhaust.

I don't know how loud the car is with my setup.
CT headers, OEM cats, Endura light exhaust. Sounds wonderful though. Sorry you can't run this.

 

[funkynsx]

When I had the Comptech exaust I eventually burned it up. I believe this was a gen I.
This was with and original CT supercharger with the 9Lb kit.

I now have a bigger blower and Low compression 3.2 motor. I have the SOS Endura light exhaust and I really like it. :smile:
I can't pass sound at Laguna with that exhaust.

I don't know how loud the car is with my setup.
CT headers, OEM cats, Endura light exhaust. Sounds wonderful though. Sorry you can't run this.

I have the endura lite exhaust now.
Its a great exhaust but a little loud for what i want.
I heard CT engineering improved the gen II exhaust by using stainless steel packing.

Maybe i need to just get a ct gen 2 exhaust and see if it holds up.
Thanks Don

 

[Mac Attack]

Your quietest, least-restrictive, and cheapest route is a custom setup with some version of Magnaflow straight-through mufflers IMO.

You can replace the canisters for $100 US each if/when they do blow out, or you can upgrade to Burns mufflers that you can repack yourself.

Dave

 

[BATMANs]

I have spent thousands of $$$ through my years on aftermarket and custom exhaust on my various car projects.

The conclusion is Magnaflow is the quietest straight through muffler on the planet.

Their secret sauce is that they use Rockwool. And that they pack it densely. It's probably one of the heaviest straight through muffler, but it's very well constructed.

Couple that with a resonated tip and it's pretty darn close to OEM at cruise. Made a difference for me getting another ticket here in Cali.

 

[funkynsx]

Is that the same manga flow muffler thats popular on rotory engines?

 

[BATMANs]

They are all the same.

http://www.magnaflow.com/02product/02muffler.asp

Oval ones are quieter.

- - - Updated - - -

Stainless Steel and fiberglass and ceramic packing is nothing compared to Rockwool.

Unless u care more about weight than sound reduction.

 

[brandonsan]

I would use the CT Gen 2 exhaust. It is actually 2 mufflers made to look like a single muffler. The divided mufflers will help with longevity and FI. I am using the Gen 2 on my Comptech 3.5 with SOS TT.