Magnaflow versus Flowmaster ~ Showdown on the Dyno

I have the American Thunder super 40 dual out on my supercharged tacoma. I think it sounds badass, so I've never understood the American Thunder hate on here. I think a big part of it is that a majority of aftermarket exhaust owners on here either had the TRD added at dealer or a magnaflow added at the local muffler place since magnaflow has a more extensive dealer network than just about anyone else. More ownership = more voices. Those who don't own use YouTube videos and second hand experience to comment on flowmasters product without ever hearing one in person.

Those are just my thoughts anyways, like I said after hearing my setup I can't understand someone hating on flowmasters.

Also, like you said, most of the flowmasters on YouTube are put on applications that are destined to fail...

 

The big Magnaflow has a really great sound!
Crush bends are fine when the pipe is sized a little larger to compensate. It might help to not transmit sound vibrations if the final tailpipe connection was also on a rubber hanger like the rest instead of welded directly to the frame.

I know my exhaust system gets longer by about 3/4" when it's hot so it's good to be hanging on rubber so that everything is free to expand without putting any stress on the components.


Greg

 

...and you have the high performance supercharged engine to fit the system.

Absolutely... I couldn't find a video of the right model Flowmaster installed on a 2.7 Tacoma!

 

Did you find the video of a super 10 on a 4 banger tacoma! Classic. I want to know the look on the shop mechanics face when he was told to install that!

 

How about this one of dual 10's on a 2.4?...

http://www.youtube.com/watch?v=n0IYWDDbP-o

No wonder so many people don't like the sound of Flowmasters. It's because one puts the right one on their truck.


Greg

 

Here's an interesting article describing two other approaches to muffler design which are completely different from the well known perforated core with sound deadening material around it... Corsa and Flowmaster.

Muffler Tech: Corsa’s Reflective Sound Cancellation vs. Flowmaster’s Delta Flow Technology

Posted by David Fuller on February 6, 2014 at 1:45 pm

Mufflers are tasked with reducing exhaust sound levels.
Ironically, muffler manufacturers have created a lot of noise and confusion when it comes to exhaust technology. Although muffler designs can be broken down into distinctive categories—chambered, turbo, glasspacks, etc.—muffler makers are quick to tout the benefits of their own, unique innovations that make these designs better.

Two of the more popular and proven muffler innovations are Corsa’s Reflective Sound Cancellation and Flowmaster’s Delta Flow Technology. Both have helped create a distinctive performance tone while reducing interior noise and fostering maximum power. But each has chosen a different (exhaust path) to get the job done.

We’ve put together this brief overview of each to help you understand how the technology works.

Reflective Sound Cancellation (RSC)



Corsa Performance Exhaust mufflers are known for reducing interior exhaust drone at low frequencies. Corsa engineers have accomplished this with something called “Reflective Sound Cancellation.”
Translation please?

The name Reflective Sound Cancellation refers to the way sound pressure waves are routed within the muffler. In Corsa’s design, unwanted low frequency sound waves are diverted through specially designed channels (see Figure A below) and then reflected, or reversed, 180 degrees into each other (see Figure B). This process causes the sound waves to effectively cancel each other, eliminating the low frequencies that cause the dreaded “exhaust drone.” It’s the same out-of-phase wave cancellation technology used by electronics companies in devices such as noise-cancelling headphones.


Figure A

Figure B












Unlike many chambered mufflers, which use baffles to reduce sound, Corsa utilizes a straight-through design with no restrictions. This straight-through configuration allows Corsa systems to reduce backpressure, maximize horsepower and torque output, and produce an aggressive sound under acceleration—all without the drone at cruising speeds. Each muffler is further tuned using exacting acoustic and thermodynamic formulas. The final design is determined using real-time spectrum analysis equipment to analyze actual interior sound at idle, acceleration, and cruise. By adjusting the size of the 360-degree air gap and the length of the pulse channels within the muffler, each muffler is fine-tuned for the specific vehicle.

Delta Flow Technology

Introduced in 1983, Flowmaster’s Delta Flow technology was also developed to cancel out exhaust noise. However, Flowmaster engineers took a different route than their Corsa counterparts, utilizing a chambered design instead of a straight-through configuration. This design gives the mufflers a distinctive performance growl which is unique to Flowmaster.



Unlike RSC, which reflects and reverses unwanted sound waves 180 degrees, Delta Flow technology incorporates a series of carefully spaced delta-shaped baffles to separate the sound waves (see left). These baffles route the separated sound waves in such a way that they re-collide with one another at precise angles, although not at 180 degrees. This partially cancels out unwanted noise, and the baffles provide additional noise reduction.

According to Flowmaster engineers, the delta design of the precisely placed baffles also creates a negative pressure within the chamber, helping to accelerate the exhaust gas flow through the muffler. As the exhaust gas is sped up through the muffler, it creates a pulling, or scavenging, effect on exhaust entering the muffler. The result, once again, is increased performance. The diagram at left shows exhaust gas and sound wave travel in a typical Flowmaster 2-chamber Delta Flow muffler.
So which one is better for your ride?

Both exhaust technologies have proven effective at maximizing performance. Most often, muffler preference comes down to your idea of what performance should sound like.

 

^^^^ We have a winner. This is all that should matter... as long as your not ruining everyone elses day by sounding like a dying jet engine at 1 am when people are trying to sleep.

 

A lot of R&D engineering, design, and testing goes into mufflers. They're all at least as good or better than the stock exhaust which is also highly engineered by vehicle manufacturers. Choosing the wrong muffler and exhaust pipe combination can only hurt your engine's performance. The one exception is headers which can actually improve performance.

Outside of that... it all comes down to which muffler sound makes your truck ~feel~ faster.


Greg

 

Been away for a while and caught up on your testing! thats crazy how small the difference was in performance. But which sound did you like better?

 

I tried to make the two dyno runs as fair and accurate as possible with the change of muffler being the only difference between them. And that was the results. I believe that they produced similar results because both the Toyota and Magnaflow mufflers were well engineered and were both well matched to the engine.

I really like the sound of Magnaflow over the stock muffler (heck, who wouldn't? ) and haven't yet installed or tested the Flowmaster. I'll be at the muffler shop day after tomorrow (Wednesday) to get the Flowmaster installed. So I should be able to let you know then which one I think sounds best. I already have videos of the Magnaflow, and will post some of the Flowmaster so that you can decide for yourself which sounds best to you.


Greg

 

I'm hoping that the flowmaster at the very least doesn't decrease HP. Also hoping there isn't drone. I had a 18 inch magnaflow on my other 2.7 and I guess it was because of the small cab, but the drone on that thing between 1.5-2K rpms and around 30 mph was absolutely terrible... it was the last thing I wanted to hear on a long commute home. I'm anxious to hear how the big flowmaster sounds.. it would be nice to have a little bit of rumble if I didn't have to hear it that much

 

I totally understand, George.
I also had an 18 inch Magnaflow installed on my truck with the stock tailpipe, and then had it taken back off in a week, because of the dreaded 2,000 rpm drone.

The 22 inch Magnaflow has no cab drone at all, because not only is it longer, but its oval section is a whole lot larger, being a 5"x11" oval as opposed to a 4"x9" oval. So it absorbs a lot more sound while still being a straight through muffler. So far it's the best sounding 2.7 muffler, in my opinion. Mellow and smooth. With no drone and no rice.

I'm pretty certain that the Flowmaster will sound slightly louder than the Magnaflow, just like the decibel chart shows. What I don't know is if it drones. That we'll find out on Wednesday. The Flowermaster incorporates a bunch of really clever design features, most notably those two differently sized Helmholtz resonators. So I'm really curious to see how it does at cancelling out undesirable sound waves... without using any sound absorbing material at all.

I find this totally fascinating how there can be two completely different design approaches utilizing completely different physical principles...

...and yet both have the aim of achieving the same results.


Greg

(edit: just noticed I passed the 2,000 post mark... )

 

Hey Tooter, what part number Flowmaster did you get? I was looking at the 942451, but now I'm thinking about the 942456

Both are 50 Series Delta Flow and 2.25", but the 942456 has a smaller case size. Seems that would be better for keeping the exhaust velocity up for better scavenging and low-end torque. Maybe I will call Flowmaster and see what they say. Oh, they're closed. Tomorrow . . .

 

There are four 50 series models.

50 series:

It has one Helmholtz resonator and one Delta Flow plate, but is a quiet muffler. It's got a really big case, and is made only for big block V8's.

Super 50 Series Delta Flow:

It's called the SUV muffler. It has a large case, one Helmholtz resonator and two delta flow plates. It's moderately loud, and made for large vehicles with large engines.

50 Series HD:

It also has a large case, one Helmholtz resonator and two Delta Flow plates. It's made for large displacement engines like big block V8's, and is aggressively loud with cabin drone.

50 Series Delta Flow:

This model has a smaller case, three Delta Flow plates, and two Helmholtz resonators. It's made for 4 and 6 cylinder passenger cars, has a moderate sound, and is relatively quiet inside the vehicle.

The first three are not recommended for our trucks. Our engines are too small, and don't produce enough exhaust for them to properly work.

I have the 50 Series Delta Flow as it has the most quieting features (two resonators and three flow plates) and is specifically recommended for our smaller engines. It's a #842452 in stainless steel, 2.25" center in/offset out. Got it off of ebay for $105 with free shipping and no sales tax. This one has a smaller case and is designed for passenger cars. And yes, I believe that it will be small enough to fill properly and will be the right size to retain exhaust gas velocity.

People run into problems with Flowmasters when they get mufflers that are too damn big for their engines and they end up sounding ratty and raspy. Or they get the loud race mufflers that sound great on high performance V8 engines, but end up sounding raggedy on regular stock engines.

Tomorrow, the Flowmaster gets installed. I'll let you know how it goes.


Greg

 

Yep, people tend to over-exhaust their vehicles. Back when cars had carburetors people would go for the biggest Holley they could fit, and then wonder why it didn't work well.

Good luck with the install, many are waiting to hear about the results!

 

LOL!

650 progressive linkage on a 265 rawrrrr!!!

I loved my 650 spreadbore on my 350. Nice little primaries for good bottom end... crack it open, and when the engine came up into 3k... hammer it to the floor and flush those toilets in back!

I swear I could see the gauge move.

 

Subd.

Went with an Aero Turbine 2525 on mine (similar straight through design Magnaflow uses) and I'm really not all that thrilled with the sound. Sounds FANTASTIC below 2000 RPM, and then like a farty Honda above that.

 

How about this FJ Cruiser with a Flowmaster 10 Series on it.

http://www.youtube.com/watch?v=8QzaIOLm83k

Honestly, who would want to drive around and have to listen to that?

In my opinion, this is where Flowmaster gets its bad reputation... from people putting the wrong mufflers on their vehicles.

When I was a kid I put a 327 Corvette block in my 55 Chevy and ran a properly sized single Holley 3310 on it with an Edelbrock highrise. Man, it ran sweet.

I'm waiting, too...
It'll be fun to see how this goes. I couldn't find any YouTube videos of a Series 50 Delta Flow on a 2.7 Tacoma, so this'll likely be a first.

Greg

 

Yeah, I also listened to a lot of the Aero Turbine videos, and they sounded like they just didn't have enough sound cancellation over a wide enough rpm range. Although I liked their looks the best... a really simple clean design. I would have liked to see them produce a longer muffler with perhaps two of their sound dividers inline to cancel more sound.

Greg

 

Tooter, thanks for doing this my friend!

+1 to ya mang