Flowmaster of no muffler?
Senior Member
Joined: May 2011
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Well shoot, I gave yuh a few plugs, -didn't really go totally against myself. Since you quoted me, you don't leave much choice. To presented the facts, -what a Flowmaster setup is doing is actually *reducing* torque on part throttle at any rpm, and reducing torque below about 3000 rpm a at any throttle position - and that is due to all those silly baffles & chambers they use as part of their "sound engineering" - all they are is impediments to airflow, and slow down exhaust gas velocity, which is why you don't see much in the way of HP gains form them, and actually lose torque, especially in the lower rpm ranges. When it comes to torque, exhaust gas *velocity* is absolutely key, and we need all we can get with these trucks.
Also which other brand are you promoting and can you provide comp data showing its performance vs FM?
Borla, Gibson, Magnaflow and Flowmaster are the big ones out there, do you have PROOF that one is better than the other?
Senior Member
Joined: Dec 2013
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From: Pasco
Senior Member
Joined: May 2011
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Senior Member
Joined: Feb 2014
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From: Northern Virginia
Not necessarily. Common sense that if you put baffles in front of exhaust gases with a high velocity will reduce the velocity. It's cause by a disruption in the flow. You want as little as possible blocking or in the way of the flow of the exhaust for maximum velocity.
Senior Member
Joined: May 2011
Posts: 655
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A lot comes down to what you're trying to accomplish, I for one can tell there is more pull from 1500rpm and up where as with a full flow it would drop off sooner. I would like a little more bottom end pull as well which is why I got the SCT tuner which gave me the bump I was looking for (could still use more, when is that not tru though).
5 Year Member
Joined: Jul 2014
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From: Everett, WA
While we are talking about what it takes and or does not take an engineer to figure out, it does not take one to see that the 10 series muffler is significantly smaller than the stock muffler. I don't see where 1 little piece of metal is going to reduce air flow more than the stock muffler.
Southern 4 Life
Joined: Apr 2013
Posts: 1,278
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From: Georgia
I have a flowmaster 50 on my 4.6 and have no torque issues of any kind. Only "performance mods" are a K&N, flowmaster, and good maintenance. I notice a little gain in torque going from a straight pipe to the flowmaster. Nothing huge or anything anybody else would notice if they didn't drive the truck on a daily basis. Point being if you get a flowmaster your truck is not going to become a slug nor is it going to kill the performance, but it will sound better. 
Senior Member
Joined: Oct 2013
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Hey guys. I currently have a Flowmaster 40 series on my truck and loving the sound. But everyone seems to like a loud truck more. I'm thinking of replacing the muffler with a pipe. Still currently have my catalytic converters. So what would sound better muffler or no muffler?