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Posted

Oh yeah, I installed my 5x8x18 Magnaflow muffler today. I decided to leave in the resonator (it's near the spare tire on 2014's) for now so I could judge volume/drone with new muffler. Before there was virtually no sound from the exhaust. Under hard acceleration you could only hear the intake. Now it sounds like a normal truck. A little bit at idle and a good clean sound when accelerating but nothing loud or "look at me" annoying. For those that want to be heard, I definitely suggest removing the resonator and going with a smaller muffler (that's if you're buying the straight flow-through style; chambered mufflers like Flowmaster might sound completely different).

I had my valve welded open and I took resonator off and installed Flowmaster Delta 40 yesterday. Just muffler with no valve modification and resonator it sounded stock. When valve was welded open it was a bit louder, but when taking resonator off that did the trick as far as getting a louder rumble.

Posted

If you leave the three catalytic converters it will not void your warranty.

Thanks. If I replace the muffler and just dump it, will it drone?

Posted

I ran mine over the axle then dumped them by the spare tire. I would recommend doing that the same. My buddy dumps his right after the muffler and its pretty loud.

  • Like 1
Posted

I ran mine over the axle then dumped them by the spare tire. I would recommend doing that the same. My buddy dumps his right after the muffler and its pretty loud.

Did you leave the resonator?

  • 3 months later...
Posted

Where exactly would you hit it if it freezes shut?

 

Look at motomedics last pic of the valve. The square piece on the side. Hit it towards the pipe. This will compress that spring and free it up. Once free you can twist that square piece to open and close the valve to ensure its moving freely.

  • Like 1
Posted (edited)

That retarded valve also freezing closed in cold places is reason enough to dump it. I mean there is no moisture in vehicle exhaust is there? Then when you shut the truck off that water would never freeze that valve from being able to open..... Having this happen on the '14's the guys at work are stuck with. Dealers solution...... make sure the valve is permanently open.

Edited by Badass69
Posted

Moisture condenses in exhaust systems regularly--notice when somebody starts a cold vehicle often a small amount of water actually poors out the tailpipe. It usually doesn't matter because exhaust systems don't usually have moving parts....

Posted

What... moisture in exhaust..... really????? Hydrocarbon combustion creates H2O..... no..... never.

 

That must be GM's standpoint anyway. Grandpas old tractor muffler flapper seemed like a great idea..... except grandpa had it to keep wildlife and water out of the muffler and manifold/ engine when it stood straight up in the air. Not to attempt to dampen sound during 1/2 cylinder time.... Its not the end of the world but for us cold climate types its something else to get rid of.

 

 

Sent from the Great White North

Posted

Moisture condenses in exhaust systems regularly--notice when somebody starts a cold vehicle often a small amount of water actually poors out the tailpipe. It usually doesn't matter because exhaust systems don't usually have moving parts....

not the first time these dampers have been put in the exhaust they used to be at the manifold years ago when EGR first started to be used to heat the engine up faster

Posted (edited)

Moisture condenses in exhaust systems regularly--notice when somebody starts a cold vehicle often a small amount of water actually poors out the tailpipe. It usually doesn't matter because exhaust systems don't usually have moving parts....

not the first time these dampers have been put in the exhaust they used to be at the manifold years ago when EGR first started to be used to heat the engine up faster

Lot less of an issue when it was designed to be closed on cold start to force exhaust through the crossover under the carb... and being right at the engine on the exhaust manifold even if it froze within a few seconds it would be free.... not the same deal when its halfway to the back of the truck and plugs the whole exhaust system off.

 

 

Sent from the Great White North

Edited by Badass69

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