So I have just got finished with installing my new headers for my 69, and by the way let me say it wasnt fun, not as much room up under there as our bronco. Anywho I now am looking to swap out the old mufflers with something for muscle car, grumble, sound. I was looking around and figured I like the flowmaster sound but am stuck between 40's or 50's. I liked the way the super 40's sounded but was afraid it might be too loud inside the car. And also it looks as though the 40's are more tuned to performance then the 50's is this true? Looking for some advice on which to go with 40's or 50's?

*also since I know it will be loud, is there any sound barriers I could install to help dampen the sound a little?

 

Look at Hooker Aero Chambers. That's what I run, agressive sound, grumble a bit, but not real loud. They sound good without attracting the attention of cops etc. And they're a straight through design that flows nearly as well as a straight pipe of the same size, the Flowmasters actually don't flow all that great so they may be a slight restriction to the exhaust, depending on how much power you make.

http://holley.com/21502HKR.asp

It has a sound clip of them on some typical Chevy. At WOT they scream pretty good, which they don't have in the sound clip, but should.

 

I am looking to stay within flowmasters, its sorta a preference thing, pride, and a deal my uncle has with the company.

 

Did you check out the sound clips in the FAQ sticky? Those might help you decide. I have the super 40's and I love them, but you're right about it getting loud inside. There are quite a few options for sound deadener now. It has been discussed here before. I'd link you to those threads but i'm on my blackberry right now and don't have my bookmarks. Try searching this forum for sound deadener and you should get plenty of results.

 

I personally do NOT like 40's. Everyone has them (just because of the name/reputation) and they're very loud. They have atendancy to drone inside the cabin as well. These old cars don't have even halfway decent sound insulation, so that amount of noise can be bothersome at best, and harmful at worst.Don't expect to have conversations with passengers while you're on the freeway.

I ended up going with the Flowmaster Hushpower II's behind my 331. They have a much more mellow 50's-ish tone, don't drone inside the cabin, and they still roar when you put your foot into it, especially above 4k rpmThe clip on Flowmaster's websitesounds almost exactly like my car. Downside is that they're very expensive.

Aside from those, I like the sound of those Aero Chambers, and my friend has a set of Dynomax mufflers on his Chevelle that I really like.

 

Ive got some 2.5 inch 40's and they are pretty darned loud.. Especially since I have no interior or sound deadener. but i like the sound..However, my wife has only ridden in the car once and she allways asks me if the car will allways be "that loud"? I just say yep.. i will probably go with some 50's later down the road depending on how the sound deadener and interior mellow out the cabin noise.. I got my pair of 40's for $50 off of a guy that had installed them and then blew his motor 2 months later, so he went with a new engine and a brand new full exhaust kit to match.. Good deal for me.. I just had to burn out the old oil that had gotten into them..