quieter exhaust

[seekhunt]

Hey there, I'm looking for some quieter mufflers for my 67 gmc with a 327 on ramshorns. I wouldn't mind something very quiet, without huge restriction to flow. Any suggestions? Pete

[trz1000]

Low noise and low restriction. Run a single exhaust, 2.5" or 3", through a large turbo muffler or a flowmaster 70 series and a resonator. Run a tail pipe half inch or more smaller than the main pipe out the side near the rear bumper. That'll be pretty quite, the flowmaster will give a bit of rumble but not obnoxious by any means.

Generally speaking smaller and longer pipes will give you more sound reduction as will bigger mufflers. Unless your 327 is pumping out some ponies, you'd have to go real small on the exhaust to have a noticeable difference. Most of the aftermarket exhaust hype is just that when you're talking about a relatively low hp street motor.

As a comparison my Jimmy, which has a mild 350 (maybe 200-225 hp), came with hedders and 2" pipes through some el cheapo turbos did not show any real benefit going to 2.5" primaries, 40 series flowmasters and 3" tail pipes other than a lot more noise. I was looking for more noise so mission accomplished. But also I am going to build a 383 (400hp goal) when this motor dies. That motor will need to breath a bit more than the 350 so I figured I'd just fab a suitable exhuast now rather than later.

If you want to keep your current setup, get the biggest turbo mufflers you can fit in the available space. You can also weld in some baffles in your tail pipes. Check out car chemistry, a little pricy for what they are but they work well.

[Mike C]

Walker DynoMax Hemi Turbos. I have Corvette Ram's Horns on mine and full 2 1/2" duals into the 2 1/2" in/out Hemi Turbos. It is really quiet at idle/cruising and has a great sound when you are in it, but never really loud. The case is 20" long on the Hemi Turbos.

[13lazer]

I'm running the 2-1/2" rams horns and I wanted my motor to be reasonably quiet. I asked the owner of a local muffler shop how I could quiet my truck down. He told me to use stock Cadillac mufflers. I found 2 Cadillac mufflers from the 80's by running an internet search. I'm very happy with how they turned out. One of my buddies told me he thought my truck was too quiet. I have to hear loud noise all day at work, so I don't mind a quiet truck.