new mufflers
Thread Starter
Melting Slicks
Joined: Jul 2007
Posts: 2,146
Likes: 31
From: Minot North Dakota
St. Jude Donor '12-'13-'14-'15, '21
new mufflers
This may sound dumb but I’m not a mechanic so I’m just throwing this out there. I’d like different mufflers for my 2013 427 vette, I don’t need x pipes or an entire system. I have NPP exhaust and want to keep it. Everywhere I look they want $1,500.00-$2,000.00 for an exhaust system. Can I just cut the mufflers off before the NPP system and just before the pipes enter the mufflers and weld new ones in place of the old. If this is feasible who sells just the mufflers. Any help would be appreciated
Thread Starter
Melting Slicks
Joined: Jul 2007
Posts: 2,146
Likes: 31
From: Minot North Dakota
St. Jude Donor '12-'13-'14-'15, '21
thats the problem, I don’t want an axle back, I just want the muffler. I don’t need any tail piping but the mufflers always seem to come with more than I need.
Platinum Supporting Dealership
Joined: Jul 2014
Posts: 722
Likes: 336
From: Rochester New York
Unfortunately no, you can't install non-NPP mufflers and install the NPP valves/tips to retain the NPP feature.
The entire NPP muffler is designed differently than a standard muffler. There are 2 air paths through the muffler, the least restrictive path is blocked when the NPP valves are closed.
A standard muffler has just one path, so your NPP tips/valves will do nothing should you weld them to a standard muffler.
If you like the NPP feature but want a different exhaust tone, you'll have to go with the B&B Fuzions or one of the other brands that offer NPP feature.
Another idea is to keep the NPP mufflers, but install long tube headers and high flow cats. The exhaust will sound more aggressive, you'll retain the NPP feature and you'll also gain some power.
Corsa mufflers are not NPP, how ever they do get louder at WOT and are tame at idle and cruise.
The entire NPP muffler is designed differently than a standard muffler. There are 2 air paths through the muffler, the least restrictive path is blocked when the NPP valves are closed.
A standard muffler has just one path, so your NPP tips/valves will do nothing should you weld them to a standard muffler.
If you like the NPP feature but want a different exhaust tone, you'll have to go with the B&B Fuzions or one of the other brands that offer NPP feature.
Another idea is to keep the NPP mufflers, but install long tube headers and high flow cats. The exhaust will sound more aggressive, you'll retain the NPP feature and you'll also gain some power.
Corsa mufflers are not NPP, how ever they do get louder at WOT and are tame at idle and cruise.
Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
What, exactly, are you trying to achieve? Just cutting off the mufflers and putting on other mufflers does not explain what your end goal is. Please explain what is wrong, and what do you want to happen?
Platinum Supporting Dealership
Joined: Jul 2014
Posts: 722
Likes: 336
From: Rochester New York
I believe he wants to install aftermarket non-NPP mufflers but use his factory NPP parts to make it NPP. Which is not feasible with non-NPP mufflers.
Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
But why? If it is to make it louder when the flaps aren't open or at low rpm without drone, there are ways to do that. It just doesn't seem like adding mufflers that are not NPP is his goal; there's some other reason which there may be a solution to w/o changing mufflers which, as you say, can't be done and keep the NPP mechanism.
Thread Starter
Melting Slicks
Joined: Jul 2007
Posts: 2,146
Likes: 31
From: Minot North Dakota
St. Jude Donor '12-'13-'14-'15, '21
Thanks for the replies and the conversation. I wanted a more aggressive tone with my mufflers but Van Bortel was right I wanted to keep the NPP system. It may be that I need to get headers and high flo cats, see what that sounds like and then reevaluate. I did not know the mufflers were made different with the NPP. With the 427 engine I thought it would sound more “racey” than it does. I think I will go the header route. AO roads thanks for looking out for me.. Thats very cool 
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Pro
Joined: Mar 2008
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From: Hurley New York
The phrase Axle Back actually refers to just mufflers. Because the only thing behind the Axle is the muffler. Now Cat back is different cause that would include everything behind the Catalytics which means the X Pipe + mufflers.
Last edited by ALS 08; Nov 21, 2014 at 07:30 PM.