Muffler Test Cheap vs. Expensive

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The 2.5" vs 3" was interesting, just goes to show that once you're moving enough air for your level of horsepower going bigger doesn't help any. Obviously it made a difference for a 600 hp engine, but I'd bet anywhere up to 400hp you'd find exactly what they did. And the 2.5" is easier to route under the car, especially at the tailpipes on these cars.

The cheap vs expensive isn't that surprising, but since they only tested two mufflers it's not really saying much. I'm sure there are cheaper mufflers than the Magnaflow's that perform better than the thrush's in the test did. But the knuckleheads make a good point, not being deaf may be more important to you than a few horsepower. I'd rather have the horsepower, but again, testing two mufflers doesn't prove that the more expensive muffler is always better. Straight pipe is the cheapest option you can get, and I'd wager it would make at least as much horsepower as the expensive muffler. So that part of cheap vs expensive doesn't hold up :D
 
Watchng it,right now... For a street car,prefer quieter mufflers... The cheapie turbos are o.k....What I have on mine. Had better luck,with longer case turbo mufflers,almost the same price as the Magnaflows. (Still don't like packed mufflers,just a personal choice). For that engine ,turbo mufflers.
 
This just reasures me that Magnaflows are the best, free flowing mufflers.
If its to loud, get an Accord.
 
How so? All I garnered from that video was that Magnaflows are better than Thrush mufflers. There are plenty of other mufflers with straight through designs.

Exactly. They only tested two mufflers. All it proves is that the magnaflows are better than the thrush's. And that a magnaflow on a 2.5" system flows enough to not limit the power of a 345 hp engine.

It doesn't prove that magnaflows are the best flowing muffler out there, or that they make the most horsepower. You'd have to compare them to everything else on the market to make that claim. And given all the sponsorship present in that video, you'd have to ask yourself if a test of everything on the market would really be unbiased. I'm betting that magnaflow and thrush are both owned by the sponsors, since they promoted the mangnaflows as the best for power, but then justified the heck out of buying a set of thrush's for the street. Still useful in the 2.5" to 3" comparison, but there's a lot of marketing in the rest of it.
 
Flowmaster I think will yield the best comprimise of power/sound on a NA Mopar engine. JMO. In tests I have seen Flowmaster yields more HP then straight pipes.
 
Flowmaster I think will yield the best comprimise of power/sound on a NA Mopar engine. JMO. In tests I have seen Flowmaster yields more HP then straight pipes.

Too bad they're the worst sounding muffler ever conceived by man. :p

More power than a straight pipe? Let's think about that for a second. They'd have to be less restrictive than a straight pipe of the same diameter for that to be true. But as we've seen, removing restriction does nothing for you past a certain point (2.5" to 3" comparison). So really, if they made more power than a straight pipe in ANY test, it would just show that your straight pipe was too small for your engine.
 
Too bad they're the worst sounding muffler ever conceived by man. :p

More power than a straight pipe? Let's think about that for a second. They'd have to be less restrictive than a straight pipe of the same diameter for that to be true. But as we've seen, removing restriction does nothing for you past a certain point (2.5" to 3" comparison). So really, if they made more power than a straight pipe in ANY test, it would just show that your straight pipe was too small for your engine.
Tests show they scavenge better.
 

Tests show they scavenge better.

Ok, lets see the tests then.

Regardless, even if the muffler was causing better scavenging in the test, it would have just as much to do with the length of pipe in the system and the design of the headers as it did with the muffler. Add a foot of exhaust pipe in there and the timing of the reflected pressure wave would change, so, the test would have to use the exact same exhaust system as the installation for the claim to be accurate in each example. Same would be true of using a different header than the test, etc. The time it takes for the reflected pressure wave from the end of the pipe to reach the chamber is pretty unique to the exhaust system, so, always using the same muffler would not always achieve the same results unless the rest of the system was identical.

Unless the tests you saw were done with the same headers and exhaust system as what you're running, there's no guarantee they're actually scavenging better on your car.
 
I was happy with the results and confirmed my thoughts on exhaust pipe sizing to engine output. The muffler part just seemed to be common sense. I would like to see the same setup with crossovers and other types of mufflers.
 
Would have liked to seen a test with the 2.5 exhaust with the turbo to see the difference compared to the magnaflo. They skipped right passed it. Pretty common knowledge that inside a turbo is only 2.5.
 
Yeah, I think that motor (not a Mopar) better represents the kind of engine a lot of us are running.

Kinda what i was thinking, a lot of guys here with teener/stocker type budget builds where i think it would have been worthwhile info for some. More of a apples to apples comparison. Most that go 3 inch are going to look at mufflers harder anyway.

But, like said, the comparison was about muffler sales. lol
 
How so? All I garnered from that video was that Magnaflows are better than Thrush mufflers. There are plenty of other mufflers with straight through designs.

Magnaflows are near the top of the performance muffler list, in pretty much every test out there.
Look it up.
 
Magnaflows are near the top of the performance muffler list, in pretty much every test out there.
Look it up.

Post it up. If you're making the claim, the burden of proof is on you. Don't be some conspiracy theory nutjob telling people on the internet to "do their research", post your source.

Magnaflows are good mufflers, but they're not the end-all, be-all.

Here's some numbers that get posted A LOT, from a mustang magazine. And, the less frequently posted actual article. Which has more info than just the numbers, plus an actual explanation of the testing done. The actual test was done on a 370 hp, '90 5.0.
Ford Mustang Muffler Comparison Test - 5.0 Mustang & Super Fords Magazine

Important to note, even though all of these mufflers were tested on the same car and the same dyno, there's still a margin of error associated with the dyno. And even if that margin of error is only 1%, it means that almost all of these mufflers performed within the margin of error. Because 1% is 3.7 hp for this test, and that would capture almost the entire spread between the different mufflers. So, from a making power standpoint, the difference is pretty much negligible for all but the best and worst performers. The rest are pretty much the same, separated by only a couple horsepower.

mufflercomparesht1.jpg

mufflercomparesht2.jpg

mufflerdecibels.jpg
 
Well........ strait through is strait through, no matter what brand. Those mufflers are compared to strait pipe and rightfully so.
 
Well........ strait through is strait through, no matter what brand. Those mufflers are compared to strait pipe and rightfully so.

Sure, but if you attribute the improvement to scavenging the information in the chart is only accurate for a 1990 5.0 mustang running without tailpipes (they didn't run any for the test to make swapping mufflers easier). That car had an improvement, but change the length of pipe, brand of header, add tailpipes, etc, and there's no guarantee you'd see a similar improvement if scavenging was truly the reason for the improvement.
 
Nutjob ?...FO
In your own article it says Magnaflows are a top pick. Next to Bassani and Borla mufflers.
How many folks here are going to run out and spend big bucks for a set of Borlas ?
And what the **** happened to an oppinion on this site ? Im not entitled to mine ?
And when did I say they were the end all be all ?
Get off my nuts dude, you dont look good on them.

Ok, so slow down and go back and read what I said. I said, "don't be some conspiracy theory nutjob". That's not the same as calling you a nutjob. Post your sources, or be compared to a conspiracy theorist telling people to do "research", because that's exactly what you're doing if you don't post the sources. Show the evidence to back up your claim.

And, of course you can have your own opinion. But say it's your opinion, don't pass it off as being supported by "tests" that you don't post sources for. You said "Magnaflows are near the top of the performance muffler list, in pretty much every test out there." So, post some tests. I only posted one, that's definitely not "every test out there". You need to post up at least a handful of tests to support the claim you made. Or just say you like Magnaflows best and be done with it, nothing wrong with that.

Finally, it's not MY article. I didn't write it, I didn't do the testing, I just posted it. I also said pretty much all the mufflers in the test are basically the same from a performance standpoint because they're only separated by a couple horsepower, which is probably covered by the margin of error on the dyno. Which is pretty much what the author of the article says too, if you bother to read the whole article. I like Dynomax ultra flo's. They aren't the best muffler in the test I posted, and I wouldn't say they're the best performing or that "every test out there" shows that. I think they sound better, and that's my opinion.

On that Mustang chart the open exhaust made the least hp and trq.

Yes, so? Scavenging theory has to do with the reflected pressure wave that comes off the end of the exhaust, and timing that pressure wave to arrive at the open exhaust valve to pull more exhaust out of the chamber. Change the length of pipe, change the header, change the firing order, all of those things change the timing that will result in the best scavenging. So to make it a really short story, it's complicated, and just using the same muffler in the test is no guarantee of similar results. You can't assume the scavenging on one car would be the same as another using different headers, exhaust pipe length, etc. Here's a pretty decent article explaining some of the theory behind that Exhaust System Technology: Science and Implementation of High Performance Exhaust Systems
 
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Magnaflows are near the top of the performance muffler list, in pretty much every test out there.
Look it up.

That's certainly not what the video shows. The video simply shows that the magnaflows were better than the Thrush mufflers under the circumstances in which they were tested. Nothing more, nothing less.
 
Because 1% is 3.7 hp for this test, and that would capture almost the entire spread between the different mufflers
Wouldn't that margin be 7 hp?
Baseline is 370, 1% less is 366.3 1% more is 373.7 , total margin is 7.4 hp?

Or am I overthinking it?
 
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I did dyno development on the Magnum engines and getting accurate, even repeatable results, for exhaust system testing is really difficult. The problem is that exhaust is very dynamic, there's a lot of pressure and temperature to account for.
Then there is usually a significant dyno to vehicle difference making it hard to apply the results to something practical.
To me the exhaust size test looks like it gives some useable insight.
The muffler testing was rather simple comparing two items but is useless without good noise attenuation data.
It was a long time ago but I was just starting to do some computer modeling, I had made some great models of the intake side but doing the exhaust was looking to be extremely difficult, maybe impossible at the time. Then I got a job change.
 
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