Can someone recommend a quiet muffler that flows well??

[FLYNAVY30]

Ive got a '72 C20 Suburban with a 6.0L LS swap....Ive been through two different sets of Flowmaster mufflers and one set of Borlas. They all sound great, but are just too loud for a daily driver. Anyone have a recommendation for a good, quiet muffler that is livable on a daily driver?

Thanks

[CastIron]

Dynomax super turbos are both quiet and flow really well. I have some of the longer-case ones (2.5") on my Chevelle and am happy with them.

[terry b]

Castlron. Can you hold a normal conversation at say 70 on the highway? Do you also run tell pipes to the back bumper. I to am looking for something a little loud when you stand on it but reasonable when in Cruise mode.

[davepl]

Another vote for dynomax. I have them on my 502 and my 402, and in both cases they're nice and quiet at idle, no drone at cruise, and yet sound loud and healthy when you open it up. Not sure how they do it, but it's the best of both worlds.

[FLYNAVY30]

Thanks guys...on the plus side, according to Summit Racing, if you buy the Dynomax, and don't like them, you can return them for a full refund within 90 days of purchase!

[terry b]

You can buy them on eBay for half price with free shipping.

[FLYNAVY30]

nice!

[slikside]

Sub'd

[Steeveedee]

If you actually want it quiet, go with a couple '70 Cadillac mufflers. Single exhaust with a 472 in front of it ought to be good enough flow, yes? I may go that route if I don't use the Dynomax mufflers when I redo my exhaust. Here is an example-

http://www.partsgeek.com/gbproducts/...ad=47433950652

Summit sells a "universal" to replace the Cadillac muffler, but I don't know how quiet they are. You can probably find that muffler cheaper than parts geek if you look around.

[weim55]

Toss a balance tube between the pipes when you install your muffler choice. It really helped smooth out the tone at all RPMs. Quieter for sure.

Steve weim55 Colorado

[CastIron]

I can easily carry on a conversation at cruising speed. Mine are in a 72 Chevelle with a 350 with headers, 2.5" pipe all the way back, and a crossover. They are the longer version of the mufflers, which I'm sure are quieter than the shorter ones. It sounds good at idle, maybe a little louder because of the headers and cam. While going down the road it's relatively quiet until you give it a lot of throttle.
The reason I picked these particular mufflers is because Hot Rod Magazine did a performance muffler comparison back in the 1990s and these were the quietest and made more power than almost all the other mufflers. They don't look fancy, but I've been very happy with them.

[special-K]

I'm wanting something with a muffled, not performance, sound for my K2500. I was thinking like the sound of a Cadillac of the era, but fitting a wide long muffler is a challenge. I'm thinking to look at truck mufflers, long round canisters. They are made to flow because power is important to a truck and not expected to be quite as muffled as a car. Just want tone without quite so throaty as a performance muffler. Think a medium duty gas engine. They sound powerful yet totally muffled

[Mike C]

The DynoMax Hemi Turbo mufflers are a great choice for a smooth deep tone with excellent flow. Have had a set on my Jimmy for nearly 20 years now. With a set of Magnaflow 5" round mufflers and a set of 2 1/2" 40 series flow masters on the shop floor that are paid for, I bought another pair of the Hemi Turbos for my short bed truck I'm swapping a 427 in.

Dynomax publishes their flow numbers for their mufflers so you can actually look up the flow for a given muffler and pipe size and you can tell if they will support your combo.

[FLYNAVY30]

Just as a reference, my exhaust system is Doug Thorley long tube headers into a 2.5 inch Flowmaster system with H pipe. Originally it had Flowmaster 40 series mufflers that sounded great at idle, but droned horribly between 1600-2500 RPM and when you got on it, sounded like a fat guy farting through a tube. I pulled those mufflers in favor of the Borla ProXS....they sounded ok, but they're just too loud for a daily driver. I swapped those for a set of the longer Flowmaster Super HP-2s. These really do sound good, but again, just too loud for a daily driver....still hard to hear the radio, or have a conversation unless you're sitting at idle.

I think Ill probably give the longer Super Turbos a shot....sounds like they're probably what I'm looking for.....now that Ive wasted hundreds on mufflers I can't use and can't return.

[Custom 68]

I'm not a big fan of Flomasters as I agree they do seem to drone. I have wanted to try the Borla since they are a bit different. I am now running Magnaflow I have a single on my truck since it is turbo and have 2 on my 04 Tahoe unfortunately I have some drone in it. I probably need to see if I can add a cross over somewhere on it. I do like the way they sound tho.
I have heard bigger is better. They may still be a straight thru design but if you get longer they will be quieter It just depends on what you can get to fit.

[kaycee]

I ran a set of dynomax turbo muffs and after a year they were rusted through at the seams . Plus they were way to quiet I put a set of summit turbos on after 2 years still look good and sound better .IDK maybe I got a bad set of dynos.

[jessemthompson]

Sounds like you need an overdrive trans. I have a short bed with spin tech mufflers going out the rear and going down the highway and I barley hear them. Open it up and it sounds like a monster. My overdrive is what keeps it tame for crushing. I think finding a muffler that flows wells and isn't loud at higher RPMs is a tall order. It also sounds like you've spent a lot of money trying to figure it out.

[FLYNAVY30]

Im running a 4L65E....RPM at 70 mph is 2100. And you're correct....I have waaaayyyy too much money into trying to find a proper muffler.

[ElKotze]

Ok, what I ended up doing is a little unusual. I don't have overdrive but 3.08 highway gears in the rear, so about 2500 rpm at 70mph. I started out with a set of Cherry Bombs right after the collectors - as you can imagine, longer highway trips were unbearable. Then I got a set of Summit Turbos and just added them to the Cherry Bombs, I wasn't worried about flow since the CB's are straight through and the Turbos are still pretty ok flowing. Most of the time I don't hear any exhaust, just a slight rumble at idle. Only time I hear anything is above 3000rpm or when I floor it, but still moderate. Didn't know if that's what your after. Almost a little too quiet for me, but it's great on long trips.

[jessemthompson]

Originally Posted by FLYNAVY30

Im running a 4L65E....RPM at 70 mph is 2100. And you're correct....I have waaaayyyy too much money into trying to find a proper muffler.

Have you tried changing the exit of the tail pipes?

[Tdrcreyn4]

sub

[Hart_Rod]

18 to 20" Magnaflows

[mchyphy]

Magnaflow 18" is nice and quiet for cruising, and sounds really good when you step on it. Get the larger case ones if you want it even quieter. I have two 17" case magnaflows coming from a 350 and exiting out the sides in front of the rear tires, and surprisingly it's quieter than I'd thought it would be. Whenever someone asks for a recommendation for mufflers, I will always say Magnaflow. Also stainless is a good bonus lol.

[schwoch1]

I just went through this with my '75 F100 with a fuel injected 4.6 in it. Had some cheapy turbo mufflers and they barked so bad I had to get rid of them. I tried Borla's, Magnaflows, Flowmasters and they were all louder than the cheapy turbo muffler. Ended up with a Walker universal muffler for it. It still has a little loudness to it and it seems to flow alright, it don't have the jet engine whoosh at WOT for sure. I did a google search for quiet performance muffler and came up with the part number, which for the life of me I can't remember right now! It's original application was early 70's GM big body cars with the big engines. I am sure that I may have lost a few HP, but I was so tired of loud exhaust I didn't care anymore!!
Hope this helps!
Mike

[BCOWANWHEELS]

2 1/2 inch early caddy. flows great and very quiet