Electric Cutouts
Thread Starter
Racer
Joined: Sep 2016
Posts: 270
Likes: 5
From: East Brunswick New Jersey
Electric Cutouts
I am not looking for power from this. Just looking to add some volume to my cat.
VMS 2.5 Cam, Kooks LTs, Kooks X, stock cat back.
Car is sooooo quiet.
While that is nice at times, other times... I really want to hear it scream.
Anyone know of a company that will not fail in NY/NJ cold winters?
VMS 2.5 Cam, Kooks LTs, Kooks X, stock cat back.
Car is sooooo quiet.
While that is nice at times, other times... I really want to hear it scream.
Anyone know of a company that will not fail in NY/NJ cold winters?
Racer
Joined: Jun 2013
Posts: 250
Likes: 12
From: Manayunk PA
Melting Slicks
Joined: Oct 2004
Posts: 2,863
Likes: 150
From: Woodland CA
The Z06 stock muffler is a dual mode exhaust (like the NPP) but was not called NPP.
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Racer
Joined: Jun 2013
Posts: 250
Likes: 12
From: Manayunk PA
My point was the OP didn't know which years fit... He could get a Billy Boat Fusion for 05-08 and add NPP in a box. Or just get an OEM NPP from a 2008 and add NPP in a box.
Instructor
Joined: Dec 2016
Posts: 225
Likes: 27
From: Washington State
When I bought my 07 z06 it had straight pipes through to resonators in the back. It was so loud I couldn't hear the wife.... I'll leave that alone. I ended up purchasing stock z06 mufflers and putting a toggle switch in the circuit so I can control the butterfly valves at will. I hear that the NPP mufflers are louder because the z06 mufflers have a perforated internal pipe instead of a solid internal pipe that the NPP mufflers have.
Instructor
Joined: Dec 2016
Posts: 225
Likes: 27
From: Washington State
Well, you don't. NPP mufflers have a different internal pipe. Z06 mufflers have a perforated internal pipe. NPP's are louder. They both operate on the same vacuum system. But they will fit either car. The NPP's are 2.5" while the Z06 is 3". So, you have to keep that in mind as some welding may be required. I really like having the switch so that I can make it loud or quiet, but I am still thinking of having some cutouts welded in.... It's never loud enough. I see both NPP and Z06 axle-backs in the classifieds quite often.
Thread Starter
Racer
Joined: Sep 2016
Posts: 270
Likes: 5
From: East Brunswick New Jersey
If the NPP is louder, I would prefer that one. Right now, the non-npp muffler from 2008 model is just way to quiet!
Are all the NPP mufflers the same? From the 08-13? The Grand Sports, ZR1, Z06, LS3?
Are all the NPP mufflers the same? From the 08-13? The Grand Sports, ZR1, Z06, LS3?
Instructor
Joined: Dec 2016
Posts: 225
Likes: 27
From: Washington State
After looking at what exhaust system your car has, if I were you, I would go with the cutouts. I think that you are after the car being loud on the inside, so you can hear it, right? Even with the butterflies open, my car is pretty quiet on the inside. It gets a little louder in WOT situations, but its still not loud like cutouts would be. There are some good threads about putting cutouts on here. Just use the search feature. Most people put them up by the transmission with some turndowns so they don't cook the rear spring.
Melting Slicks
Joined: Oct 2004
Posts: 2,863
Likes: 150
From: Woodland CA
The mufflers on the Zr1/Z06 is different (not called NPP). Has 3 inch tubing which would require additional modification to bolt up to your 2.5 inch x-pipe.
From your first post, I see you have Kooks headers with the Kooks X-pipe. And while that pipe is 3 inches, the X-pipe is reduced to 2.5 at the outlet to be able to bolt on to the stock LS3 muffler.
Racer
Joined: Nov 2016
Posts: 478
Likes: 18
From: Cape Coral Florida
All NPP mufflers are the same (2008 – 2013 LS3) and will be a direct bolt on to your car.
The mufflers on the Zr1/Z06 is different (not called NPP). Has 3 inch tubing which would require additional modification to bolt up to your 2.5 inch x-pipe.
From your first post, I see you have Kooks headers with the Kooks X-pipe. And while that pipe is 3 inches, the X-pipe is reduced to 2.5 at the outlet to be able to bolt on to the stock LS3 muffler.
The mufflers on the Zr1/Z06 is different (not called NPP). Has 3 inch tubing which would require additional modification to bolt up to your 2.5 inch x-pipe.
From your first post, I see you have Kooks headers with the Kooks X-pipe. And while that pipe is 3 inches, the X-pipe is reduced to 2.5 at the outlet to be able to bolt on to the stock LS3 muffler.
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
Here is my write up with pics and instructions on my QTP cutouts. I've had them 10 years and love them. The should great in the car when open, and when closed with stock mufflers the car is whisper quiet which is nice when I want to be quiet.
https://www.corvetteforum.com/forums...-on-my-c6.html
https://www.corvetteforum.com/forums...-on-my-c6.html