Cheapest/ Best Exhaust Mod
Thread Starter
Instructor
Joined: Mar 2014
Posts: 125
Likes: 0
From: Texas
Cheapest/ Best Exhaust Mod
I own an '05 Corvette C6 with an LS2 engine. Bone stock looking to get a few things done. I want to spend my money on a tune, intake, but would really like a new exhaust system but they're so expensive. I've seen stock modded exhaust where they drill holes in the muffler and welding on circular pieces, but that's not really up my alley either cause then I'm out a new exhaust system if things don't go well. I was wondering what the best way to get a better sound from the exhaust would be without spending 700-800 dollars. If there is a muffler that would be better or an X pipe, something simple and not costly that could get the best sound boost.
P.S: Running straight piped isn't an option, too loud.
P.S.S: Would like a good sound but not too obnoxious.
P.S: Running straight piped isn't an option, too loud.
P.S.S: Would like a good sound but not too obnoxious.
Melting Slicks
Joined: Nov 2010
Posts: 2,626
Likes: 195
From: On the east coast we drive until we die
http://forums.corvetteforum.com/c6-p...-mufflers.html
I would have done the NPP if I didn't already have Borlas. Better jump on this sale because it will go quickly at that price. Keep in mind you will still need the vacuum install kit and controller but you're still well under $800.
I would have done the NPP if I didn't already have Borlas. Better jump on this sale because it will go quickly at that price. Keep in mind you will still need the vacuum install kit and controller but you're still well under $800.
Thread Starter
Instructor
Joined: Mar 2014
Posts: 125
Likes: 0
From: Texas
I was thinking about this, but how much meaner is this NPP system? I guess I'm not really sure how it works 100% it's not like cutouts is it, where it dumps the exhaust before the mufflers? If not what is the open doing as opposed to the closed? And how much did this run you installation + purchase of NPP in a box and system. (If you don't mind me asking)
Drifting
Joined: Jul 2010
Posts: 1,400
Likes: 39
From: Atlanta Georgia
NPP in a box controller I think is $100....it's been a while. Be sure to get the "easier adapter" for the vacuum port that uses the front hole in the intake manifold. It's $15 or $20 more than the kit without it, but super easy to install.
I got used NPP mufflers shipped for a total of $600 or so. I've seen Z06 mufflers (you would just need a 2.5 inch to 3 inch adapter pipe), for as low as $350 on here.
Did the installation myself. Easy to do. If you can cut a pipe, use band clamps, or have it welded together to connect to existing exhaust, that's all you have to do.
I'm sure a local muffler shop can install the mufflers for $100 if you can't do it yourself. If they charge more, go somewhere else.
I got used NPP mufflers shipped for a total of $600 or so. I've seen Z06 mufflers (you would just need a 2.5 inch to 3 inch adapter pipe), for as low as $350 on here.
Did the installation myself. Easy to do. If you can cut a pipe, use band clamps, or have it welded together to connect to existing exhaust, that's all you have to do.
I'm sure a local muffler shop can install the mufflers for $100 if you can't do it yourself. If they charge more, go somewhere else.
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 265
From: St. Louis, MO
St. Jude Donor '08
You might look into QTP Cutouts. Trick is to find an exhaust shop to weld them in for you. My guy was kind of expensive but 7 years later they are still going strong and sound better in the car than NPP or Z06 mufflers, particularly if you put in a cam.
http://forums.corvetteforum.com/c6-t...-on-my-c6.html
http://forums.corvetteforum.com/c6-t...-on-my-c6.html
Had QTP cutouts installed by Florida Performance in Fort Lauderdale. Overall very pleased with the job Rob, the shop owner, did. This was his first C6 and he found a great place to put them and made the custom mandrel bent Y-pipes to maximize flow from the cutouts. We found no way to put them right after the collectors but they fit well by the trans. I have the DTE brace too but it wasn't in the way.
Installed the wiring myself along the drivers side rocker panel, behind seat then out the wheel well under the carpet. Removed the rear inner fender and drilled a small hole in the wheel well then ran the wire down to the cutouts. Hardest part is finding a hot wire when the ignition is on on these C6's. I ended up tapping the seat heater fuse as others here have done.
They are loud and DEEP when open at idle. I've actually heard louder exhaust though, I was kind of surprised they are not louder. I think it is because of the turn downs and the fact that I have cats and the pipes are pretty long before the cutouts. On the track they have a nice race car sound - I'd say like Borla Stingers plus 25%. When you open them at a stoplight you will turn heads, that's for sure.
Overall happy with the mod, it gives me quiet during my morning drive but loud when I'm at the track which is what I wanted.
Here is a video of idle with cutouts open and closed. The gain on the mike makes the closed sound much louder than it is, it's really quiet with factory mufflers even with my cam.
Here are some pics:
Installed the wiring myself along the drivers side rocker panel, behind seat then out the wheel well under the carpet. Removed the rear inner fender and drilled a small hole in the wheel well then ran the wire down to the cutouts. Hardest part is finding a hot wire when the ignition is on on these C6's. I ended up tapping the seat heater fuse as others here have done.
They are loud and DEEP when open at idle. I've actually heard louder exhaust though, I was kind of surprised they are not louder. I think it is because of the turn downs and the fact that I have cats and the pipes are pretty long before the cutouts. On the track they have a nice race car sound - I'd say like Borla Stingers plus 25%. When you open them at a stoplight you will turn heads, that's for sure.
Overall happy with the mod, it gives me quiet during my morning drive but loud when I'm at the track which is what I wanted.
Here is a video of idle with cutouts open and closed. The gain on the mike makes the closed sound much louder than it is, it's really quiet with factory mufflers even with my cam.
Here are some pics:
Thread Starter
Instructor
Joined: Mar 2014
Posts: 125
Likes: 0
From: Texas
You might look into QTP Cutouts. Trick is to find an exhaust shop to weld them in for you. My guy was kind of expensive but 7 years later they are still going strong and sound better in the car than NPP or Z06 mufflers, particularly if you put in a cam.
http://forums.corvetteforum.com/c6-t...-on-my-c6.html
http://forums.corvetteforum.com/c6-t...-on-my-c6.html
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 265
From: St. Louis, MO
St. Jude Donor '08
Me too, but I found a guy on the forum who had gland this tiny shop that rebuilds Ferrari manifolds and he did it for $400. Took him only 2hours so a good hourly rate for him but he did a great job. All in I was about $650 for a great sounding exhaust.
Maybe you can find a small shop willing to do it. My chain stores wouldn't do it.
Maybe you can find a small shop willing to do it. My chain stores wouldn't do it.
Drifting
Joined: Oct 2006
Posts: 1,608
Likes: 7
From: DELRAY BEACH FLORIDA
St. Jude Donor '10-'13
Iv'e got a modified pair of ZO6 mufflers off my 08 A6 coupe. They work great and sound great. They work on either the six speed or the automatic. The three inch pipes were replaced with stock 2 1/2". They are just sitting in my storage unit. Would be difficult and costly to ship. If your local(south Florida)...these would do the trick. I'll take $350.00 picked up in South Florida. If this works for you...call me or PM me. 561 654 4247.
Race Director
Joined: Dec 2013
Posts: 12,505
Likes: 3,631
You change muffler for sound, not HP gain since there is so little to be had there with different mufflers or even straight piping since the its the other end of the exhaust that is the problem.
If you are looking for HP gains, then long tube headers with high flow cats instead. Even with the OBX high flow cat'd headers system, you will be picking up at least 25 to 30hp from them with the tune. Hence the flow restriction/problems is taking place with the stock exhaust and cat's, and not at the end of line with the mufflers.
So to break is down once you tune the LS2,
Base motor you can pick up around 15hp with just a tune.
Headers and high flow cat'd X pipe, around 25 more with the tune.
New air filter, a few hp more at most with the tune.
New mufflers, another few HP at most with the tune.
If you are looking for even more HP, then fast intake will yield around 20hp more (intake manifold the restriction part of the match and why just adding in a new air filter system does not yeild high HP gains),but it, like cam'g or porting heads is not cheap.
If you are looking for HP gains, then long tube headers with high flow cats instead. Even with the OBX high flow cat'd headers system, you will be picking up at least 25 to 30hp from them with the tune. Hence the flow restriction/problems is taking place with the stock exhaust and cat's, and not at the end of line with the mufflers.
So to break is down once you tune the LS2,
Base motor you can pick up around 15hp with just a tune.
Headers and high flow cat'd X pipe, around 25 more with the tune.
New air filter, a few hp more at most with the tune.
New mufflers, another few HP at most with the tune.
If you are looking for even more HP, then fast intake will yield around 20hp more (intake manifold the restriction part of the match and why just adding in a new air filter system does not yeild high HP gains),but it, like cam'g or porting heads is not cheap.
