As for the performance thing though, I doubt you'd feel any difference if someone chopped out your glasspack and replaced it with a chambered muffler whilst you were asleep. 
Flowmaster....
Hotshot
Joined: Sep 2001
Posts: 11,958
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I have also read a bunch of different muffler tests that show that Flowmaster is one of the worst for performance.
The difference on a stock or mild motor is probably not very noticable, but it is there.
Hotshot
Joined: Sep 2001
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The longer ones are deep and mellow. Most people have the short ones because they want it to be loud. Loud is not necessarily better.
Postmaster
Joined: Jan 2009
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Yeah everone has there own idea about exhaust systems . I just don't like loud raspey exhaust , i run a very short system that ends at the end of the cab so i don't have alot of room , Similar to a mustang 2 1/2 duals H pipe then mufflers thats it. I don't think i have a problem with backpressure with the 44s . To elimanate back press at the mufflers just run a bigger pipe before the mufflers,then a bigger muffler , like 2 1/2 to 3" pipe & muffler . I never had a problem with drone , i think Conanski might be on to something when he said he just moved his muffler closer to the front of the system & it elimanated the drone ?? ...Lew
New User
Joined: Nov 2009
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I put the flowmaster 40 series on my 302 w/o takin out the cats .... it did not give it the sound i was looking for...(actually after a year i really dont think it sounds any different than the stock one)..im looking at doing a strait pipe with resonators....npd sells some like it. but do yall think it would sound good?
New User
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Posting Guru
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i wouldn't gut the cats because that still is a restriction because your exhaust is hitting an open area then getting necked down again to go through the outlet of the cat. If you don't want cats just don't run them, there are plenty of ways to get around emissions testing just look up how many miles you have to drive under to be emissions exempt and adjust accordingly
Hotshot
Joined: Sep 2001
Posts: 11,958
Likes: 228
Yeah everone has there own idea about exhaust systems . I just don't like loud raspey exhaust , i run a very short system that ends at the end of the cab so i don't have alot of room , Similar to a mustang 2 1/2 duals H pipe then mufflers thats it. I don't think i have a problem with backpressure with the 44s . To elimanate back press at the mufflers just run a bigger pipe before the mufflers,then a bigger muffler , like 2 1/2 to 3" pipe & muffler . I never had a problem with drone , i think Conanski might be on to something when he said he just moved his muffler closer to the front of the system & it elimanated the drone ?? ...Lew
Conanski still doens't like his Flowmaster 50. I believe that is what he has.
He did say that moving the muffler forward did greatly reduce the interior resonance. That just seem like it would do the opposite to me.
Hotshot
Joined: Sep 2001
Posts: 11,958
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If you have both the stock cats, just straight pipe it and see how you like it. It sounds fairly good this way. But you have to run tailpipes. If you dump it like this it just sounds like broken exhaust.
