No mufflers
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Joined: Aug 2009
Posts: 53
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From: Tucson Arizona
No mufflers
All,
Not a mechanic by any means, have had a few people comment on my setup. Some say good, some say bad. What I have is an 05 C6 with the LS2, and what I have done was put some 07' Z06 3" headers, 07 Z06 cats, and 07 Z06 H pipe which lead to dual 3" dumping out the back with no mufflers. So went from the stock 2 1/2" setup to the 3" Z06 setup with no mufflers. Also have an intake, in regards to back pressure or whatever else may be involved, could this potentially damage my valves or anything else not having mufflers? I have driven about 4-5k miles on the setup, no check engine lights, no tuning and seems to run great. Just want an opinion from some guys that know what they are talking about rather than the drunk friend on the weekend running his mouth. Thanks in advance.
Not a mechanic by any means, have had a few people comment on my setup. Some say good, some say bad. What I have is an 05 C6 with the LS2, and what I have done was put some 07' Z06 3" headers, 07 Z06 cats, and 07 Z06 H pipe which lead to dual 3" dumping out the back with no mufflers. So went from the stock 2 1/2" setup to the 3" Z06 setup with no mufflers. Also have an intake, in regards to back pressure or whatever else may be involved, could this potentially damage my valves or anything else not having mufflers? I have driven about 4-5k miles on the setup, no check engine lights, no tuning and seems to run great. Just want an opinion from some guys that know what they are talking about rather than the drunk friend on the weekend running his mouth. Thanks in advance.
Thread Starter
Advanced
Joined: Aug 2009
Posts: 53
Likes: 0
From: Tucson Arizona
Thanks, I have had a lot of know it all's commenting on things from tumbling exhaust, to not enough back pressure and my valves are done for, to burning up this or that. Just needed a solid opinion because after a while I start to think....**** maybe I am trashing my prized possession... 
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Running without mufflers will have zero effect on your valves. Exhaust leaks next to the motor, like a bad exhaust manifold leak could have an adverse effect on valves, but running without mufflers won't hurt anything except maybe your ears.
Tech Contributor
Joined: Oct 1999
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From: Charlotte, NC (formerly Endicott, NY)
I don't see how you could be hurting anything. Think of it this way. Stock LS3s and LS7s run with open exhausts when the muffler valves are open. People have been moving the Z06/NPP style exhaust to LS2 cars for quite some time with no issues. If you were running the Z or NPP mufflers with the valves open you would be running an open exhaust. Those mufflers are basically straight through pipes when the valves are open. The fact that they neck down to 2.5 inches at the muffler inlet probably doesn't mean much that far down the exhaust stream where the exhaust has cooled quite a bit.
Bill
Bill
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Joined: Apr 2010
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you may lose some torque down low possibly, but it would be minor, having some backpressure is a good thing, you have cats, so that is enough.
I have lg pro headers (catless) with slp lm1 (just resonator, no muffler) and it's as loud as it gets, i do wonder if i lost any hp/tq down low because of it though, i have good dyno numbers, but don't have before/after to compare sadly.
I have lg pro headers (catless) with slp lm1 (just resonator, no muffler) and it's as loud as it gets, i do wonder if i lost any hp/tq down low because of it though, i have good dyno numbers, but don't have before/after to compare sadly.
