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I'm new to the Corvette world and am looking to buy a C6 soon. I know I want to put an exhaust system on it straight away. Since I'm new to Corvettes I have no idea what I need.
I'd like to do the entire exhaust system at once, I want catless and loud but not droney on the highway.
It seems that headers and x pipe is a good way to go. Some folks like a loud car, some don't. Keep in mind that the vette you get might have dual mode exhaust which adds actual butterfly valves at the failpipe on the center two tips. I like this feature because keeps the noise level down until you get midway into the power band and it give a bump in the power. Some folks leave disable this to keep them open all of the time(keeps it louder) and some add a mild to wild switch so you can select the mode at random. From what I have read, there isn't much performance gain of swapping past the X pipe.... will only change the sound. Unless you have money burning a hole in your pocket, I suggest doing headers and X-pipe and seeing how you like it. You can always swap the rest if your not content.
I've had NPP, Z06, and ZR1 bi mode mufflers. Also had a pair of Corsa Sports. None of the bi mode mufflers drone in the quiet mode. The Corsa's don't drone either. All of these were on Vettes with long tube headers and no cats. All were cammed and over 500 rwhp. GM claims, compared to the base mufflers, the bi mode NPP mufflers were worth all of 6 hp on a stock LS3 powered Vette. That figure might go up if/when you add horsepower.
Kooks headers WITH catted x-pipe going into NPP exhaust with a Mild to Wild switch. Cats won't cost any HP and without them you will probably get some drone. NPP exhaust will give you both quietness when you want it and loud exhaust when you want with Mild to Wild switch.
And if you are looking to get a C6, I recommend getting a wide-body version that already has an NPP exhaust. Either a Grand Sport or a Z06 (or ZR1 if you can swing it).
Last edited by Spaceme1117; Sep 26, 2020 at 08:42 AM.
I've had NPP, Z06, and ZR1 bi mode mufflers. Also had a pair of Corsa Sports. None of the bi mode mufflers drone in the quiet mode. The Corsa's don't drone either. All of these were on Vettes with long tube headers and no cats. All were cammed and over 500 rwhp. GM claims, compared to the base mufflers, the bi mode NPP mufflers were worth all of 6 hp on a stock LS3 powered Vette. That figure might go up if/when you add horsepower.
Is NPP and dual mode the same thing? I sometimes see the terms used like they might be different, "I've had NPP, Z06, and ZR1 bi mode mufflers."
Go with High flow cats on the X pipe. Your going to lose about 4HP, but cabin will not be stinking of unburt fuel every stop light.
Note, wait to swap out to high flow cats from the stock cats, when you install Long tube headers and new X pipe with high flow cats.
As for mufflers, Borla Atak. Your going to get the louder deeper tone muscle car sound you want, but will not have any drone.
If you want a more Higher V12 type tone and increase sound with no drone, then Corsa extremes, but you will not get the head turning start up sound like you do with Atak mufflers. Also to note, both system will work with both stock X pipe, and when you swap out to long tube headers with high flow catted X pipe.
Short of the above, then its a hit or miss if the system will have drone, which even the NPP mufflers have drone in loud mode.
Hence if the system ends up with drone, you will be ripping it off the car inside 3 weeks, no mater how much of a money lose you have to take in the end.
Also to add, when you do go to Headers with High flow cats, the mufflers/exhaust system is going to be louder. Because of this, most will drop down on the mufflers output sound to a sports type level, which kicks the levels back up to the louder mufflers with the headers in play.
And to conclude, mufflers are only going to change the sound of the car, not add any more power. To get more power from the exhaust system, then long tube headers are needed, since they scavenge more exhaust from the engine to pick up around 25HP in general.
Is NPP and dual mode the same thing? I sometimes see the terms used like they might be different, "I've had NPP, Z06, and ZR1 bi mode mufflers."
NPP's have the smaller mid pipes and come optional on LS3 powered Vettes, whether Grand Sport or base narrow body coupe. Z06 and ZR1 mufflers are for the larger 3" mid pipes and come standard on the Z06 and ZR1 models. All three are dual mode and work the same. The early Z06 mufflers were a little quieter than the NPP and ZR1 mufflers. Later model Z06 and and ZR1 mufflers are the same. I think they started using the same mufflers for the Z cars in 2011. You can tell them apart by looking on the inside of the tips. Later Z06 and ZR1 mufflers had perforations on the inside of the tips.
I have LG headers & cam and recently changed my stock exhaust to z06 bi-mode but no switch, so it's always "open"...sounds GREAT at idle! But terrible drone 1200-1700ish rpms when driving around. Not so bad around town, but on the interstate the drone is obnoxious in 6th going the speed limit. Definitely go with the switch to open/close if you go this route. I'm doing that soon.
NPP's have the smaller mid pipes and come optional on LS3 powered Vettes, whether Grand Sport or base narrow body coupe. Z06 and ZR1 mufflers are for the larger 3" mid pipes and come standard on the Z06 and ZR1 models. All three are dual mode and work the same. The early Z06 mufflers were a little quieter than the NPP and ZR1 mufflers. Later model Z06 and and ZR1 mufflers are the same. I think they started using the same mufflers for the Z cars in 2011. You can tell them apart by looking on the inside of the tips. Later Z06 and ZR1 mufflers had perforations on the inside of the tips.
I greatly appreciate the explanation. I could not find that info when I searched it.
If you want loud, I have 1 7/8” headers, off-road x pipe, and Borla S Type II and its sooooo dam loud. If you want loud this will do it. It’s almost too loud for my liking but I bought it so I have to deal with it. If I could exchange it it, I would. Lol!!
CamarosRus, that looks fantastic. How about a pic that shows how low it hangs.
From first hand experience, I can tell you for sure that Kooks, LG, and Pfadt headers tuck up very nicely. I've heard the ARH does too. Tx Speed headers are known to hang low. It's not uncommon to see them for sale on the forum with one of the primaries having a dent.
Is NPP and dual mode the same thing? I sometimes see the terms used like they might be different, "I've had NPP, Z06, and ZR1 bi mode mufflers."
NPP is the GM 3 character build code for bi-mode mufflers. It's been appropriated as a term to describe mufflers with valves that can re-direct exhaust gasses to two different outlets in the same manner as the term "exhaust" has been appropriated to mean a muffler.
The NPP option was first available in '08 on base models and later on cars with the LS3 or LT1 engines. The '05 and newer C6 and C7 cars with other engines have the same design mufflers, but are standard vs an option and therefore not "NPP", but still a bi-mode muffler.
From first hand experience, I can tell you for sure that Kooks, LG, and Pfadt headers tuck up very nicely. I've heard the ARH does too. Tx Speed headers are known to hang low. It's not uncommon to see them for sale on the forum with one of the primaries having a dent.
I've read that about the TSP headers and at this point I intend to avoid them for that reason. I installed Speed Engineering on my previous F-body and they were great. But being an import, I understand why folks don't promote them.
Originally Posted by HOXXOH
NPP is the GM 3 character build code for bi-mode mufflers. It's been appropriated as a term to describe mufflers with valves that can re-direct exhaust gasses to two different outlets in the same manner as the term "exhaust" has been appropriated to mean a muffler.
The NPP option was first available in '08 on base models and later on cars with the LS3 or LT1 engines. The '05 and newer C6 and C7 cars with other engines have the same design mufflers, but are standard vs an option and therefore not "NPP", but still a bi-mode muffler.
Nothing HANGS LOW......with the ARH 1 7/8" & 3" Catted X Pipe
With the OE system Removed You should install the DEI, Tunnel
Insulation Kit.
Disclosure: ARH advises per their instructions that the Right Side
Frame FLANGE may need to be trimmed .....Which was my case.
This requires a Harbor Freight ($10) 90 angle cut off tool and then
a Sanding Disc to Smooth the sharp edge)
Message me for details
You also need to order misc wire and tubing insulation materials
Installing Headers while only elevated on Jack Stands will be a "bitch"
You would NEED a Helper to constantly feed you tools etc.
I have a two post lift and it is the BEST way to do this
Last edited by CamarosRus; Sep 27, 2020 at 04:16 PM.
Your answer lies at the bottom of the page. PN 70501367 includes everything for $2,216.95 for a Z06. I would assume they have the comparable package for LS2/3 cars for a similar price.
A brief glance on the C6 parts forum, found a new/unused LG 1 3/4" Super Pro system for $1K. You'd only need to find OEM 2.5" bi-mode mufflers to be complete.
No matter what brand headers you get, the difference would be about 3 HP max and would have similar installation time/cost.
Used systems generally sell for about half as much as new, because they don't depreciate at the same rate as the used car they're on.
That's a complete system which is great but it's got the dual mode things on it and this car didn't look like it had those on it, I got down and checked and didn't see any valves.
Exhaust system reccommendations?
