Hi All,

Seems that loud bang I posted about yesterday blew my exhaust up . Out in the sunlight I could see that my muffler has buckled and has crease marks on the side. It was on its way out to be fair, I was going to replace the lot in the summer.

So I'll be needing a new exhaust. I'm going to take this opportunity to upgrade it. I'll be running 2 1/4" from the manifold to the muffler, and 2" tailpipe.

I was wondering if anybody could recommend a muffler for my application? I want it free flowing and quiet, no drone at motorway speeds.

I'm aware that this has been discussed at considerable length with different people having different experiences.

I know Ted swears by Magnaflow and Dan swears at it. Is your exhaust still dead quiet Ted?

My current feeling is that I can't do too badly with a large stockish box as Dan suggests. I can get a Continental MkVII box here which has the advantage of correct in and out sizes and very well priced (for the UK).


My gut instinct is that the muffler doesn't make as much difference as the choice of pipe sizes anyway. But if anyone can say otherwise I'd be glad to hear it.

All the best,
60 Ply

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1960 Plymouth Belvedere 4 door sedan
Stock 60 225
Push button 3 speed Torqueflite
Right Hooker

Yes it is and my wife loves it. However, I don't think Dan ran the longer body version. The 14" body will make a roar around 2700 to 3000 going up a hill. On the level/freeway the 14" MagnaFlow is ok but marginal for a 6 cylinder . The longer body 18" version is quieter. The 22" is better yet. Mine has a 2.25" inlet and outlet with a 2.5" internal pipe with many more holes exposed to the packing which helps absorb more noise. I am also running a 22" long 2" diameter resonator along side the gas tank with a turned down tip. So my set up is very free flowing and stealthy. Even the 1980 barn find stock motor has more power. Mileage is not bad either on this stock motor, at 22 mpg around town and to work, little to no freeway driving. Once I am on the freeway the mileage goes way up. Cruise is 2500 to 2750.
Your right on about the larger diameter pipe making a difference in noise level. That is just physics.......and we need to design the exhaust system accordingly. Any boxy type muffler with out packing is going to make more noise unless it is very long (longer than 14") so it has a chance to cancel/difuse the noise.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Hey Ted,

Thanks fr the reply. What you say that exhaust gives you is what I'm going for really. My only concern (apart from cost) is if it lasts. I've seen a few posts around this board that said it was great for the first four or five months then started to play up. How long have you been running it?

Also, you refer to a 'resonator'. Not a term I'm familiar with, is this a second muffler like a glasspack/cherry bomb?

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1960 Plymouth Belvedere 4 door sedan
Stock 60 225
Push button 3 speed Torqueflite
Right Hooker

Ted's guess isn't right; mine was the 22"-body version. And it had an obnoxious drone at cruising speed even after adding a resonator and trying a smaller tailpipe.
Excellent price on an ideal choice. Get it! Spend the savings on nice pipeworks.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

At that price it's 'worth a punt' at the very least.

It's strange how people's mileage varies so much regarding mufflers. Suppose there's great variation in people's interpretation of noise levels and the sound deadening actually in the car.

Did you get my email Dan?

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1960 Plymouth Belvedere 4 door sedan
Stock 60 225
Push button 3 speed Torqueflite
Right Hooker

The muffler is stainless steel and it still looks like new. As far as time, I installed it last August and the sound has not changed at all and is very quiet like the stock system but freer flowing.
No, this is like the resonator on my wife's 72 Imperial. It is not a glass pack. There is no fiberglass in it to burn out or absorb moisture. The best way to explain it is that it is a perforated 2" pipe inside a 4" diameter shell.
I am with Dan on this one. I would get the Continental....the price is great! Looks like a good match for daily driver. My system is much more expensive and I built it more for drag racing (high flow) as well as a daily driver. My car will spend allot of time at the track and I wanted max flow but very quiet.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

The two open questions ("What's a resonator?" and "Why is Ted's quiet and Dan's was loud?") are really two angles on the same issue. A resonator isn't a particular kind of device, it's simply a secondary muffler of one type or another (Baffles & chambers, glasspack, whatever) placed ahead of or behind the main muffler. Its construction, size, configuration, and placement are all selected to damp noise of particular frequencies. These, in turn, arise because of the characteristics of the engine and the whole exhaust system—pipe diameter and length, main muffler characteristics, etc. Just like a pipe organ, different lengths and diameters of pipe will resonate at (and amplify) particular frequencies. And this is why a muffler that's almost stock-quiet on one car with a given engine may make objectionable noise on another car, similar but not identical, with the same kind of engine. Ted was lucky that the configuration of his car's exhaust system and the placement of the muffler (dictated by undercar space) was such that it effectively damps the objectionable frequencies even with the straight-through design of the Magnaflow muffler. I wasn't lucky; that kind of muffler wasn't effective as it had to be placed in my car. Stock-type mufflers (baffles/chambers etc.) are much, much less sensitive to placement.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.