**DISCLAIMER** I am in no way affiliated with Flowmaster in any way shape or form. I am simply writing this to help people be better informed in choosing which 40 series muffler is best for them since they are probably the best selling muffler out there. This write up is based on personal first hand experience on each muffler as I have personally owned and installed each one of them. I have a shed full of these mufflers to prove it. People need to know there are 4 different types of 40 series mufflers on the market, each with their own distinctive sound. With that said, lets take a look at each. I am posting these in order of loudest to quietest, and I will explain what makes each unique. There is a huge difference in these. Do not think the differences are small because they are not. Choosing the right 40 series muffler could be the difference between you hating the muffler versus loving it.
-Flowmaster Original 40 Series Muffler
The muffler that made the 40 series famous. This muffler has a single sound deflector which gives you the signature sound of a Flowmaster, but lacks the Delta Flow Technology. What does this mean? This means the muffler is not only loud, but drones like a mofo. This muffler is what leads to people complaining about how much 40 series mufflers drone. While they do drone, they give you the sound you're wanting while yelling "look at me!". It's worth noting that the patent ran up on this muffler, so you will see knock offs from all kinds of makers out there. NOTE THAT THE KNOCK OFFS ARE USUALLY CHINESE MADE. This means the welds are cheap, and if you google some of these knock offs, you will see people complaining that the internal deflect becomes unwelded inside the muffler. While the knock offs are cheaper, I would recommend you buy genuine Flowmaster Original 40 series mufflers to not only support AMERICAN JOBS, but to ensure you get a quality product WELDED into your exhaust system. To note, some knock offs are Thrush Welded, V-Flow, Raptor, ect...
Note the internals. Single deflector design lacking the Delta Flow technology which causes it to not only be loud, but can drone A LOT.
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Next up and second loudest is the Flowmaster Super 44. I personally run this muffler currently as it tends to be deeper sounding then the Original 40 and Super 40 mufflers. It will give you the 40 series sound, but does not sound as "hollow". The tone is deeper while utilizing Delta Flow Technology. This means cruising drone is lessened, but not minimized fully, and gives a nice deep throaty sound. This muffler is slightly louder then the Super 40, while killing some of that drone the Original 40 has. Note the below- this muffler has 2 medium sized sound deflectors.
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Next up we have the Flowmaster Super 40 series muffler. It's important to note that this muffler is used in Flowmaster's American Thunder series cat back systems. This muffler is much more true to the classic Flowmaster sound. The sound is more "hollow" while utilizing Flowmaster's Delta Flow technology. This means you get the sound of the original 40 series muffler without the ALL the drone that comes with it. What I am saying is there is still drone, but not nearly as much. Take a look at the below. You will see two medium sized deflectors followed by a single small deflector
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Last, but not least, is the Flowmaster Delta Flow 40 series muffler. It's weird that's it's named this way as the top two mufflers utilize the Delta Flow technology, but this muffler takes it to the extreme, I guess you could say. This muffler is significantly quieter then all the mufflers stated above, but still gives you that signature sound when you get on it. This muffler almost kills all drone, and you will even see some people complain this muffler is too quiet. See below - this muffler utilizes a large deflector, medium deflector, then a small one.
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And now you know. The next time someone complains about their 40 series muffler, ask them which 40 series exactly do they have? This could help pinpoint exactly why they hate it and now you can offer a suggestion of how they can keep their 40 series sound while keeping it at a sound level they can enjoy.
-Flowmaster Original 40 Series Muffler
The muffler that made the 40 series famous. This muffler has a single sound deflector which gives you the signature sound of a Flowmaster, but lacks the Delta Flow Technology. What does this mean? This means the muffler is not only loud, but drones like a mofo. This muffler is what leads to people complaining about how much 40 series mufflers drone. While they do drone, they give you the sound you're wanting while yelling "look at me!". It's worth noting that the patent ran up on this muffler, so you will see knock offs from all kinds of makers out there. NOTE THAT THE KNOCK OFFS ARE USUALLY CHINESE MADE. This means the welds are cheap, and if you google some of these knock offs, you will see people complaining that the internal deflect becomes unwelded inside the muffler. While the knock offs are cheaper, I would recommend you buy genuine Flowmaster Original 40 series mufflers to not only support AMERICAN JOBS, but to ensure you get a quality product WELDED into your exhaust system. To note, some knock offs are Thrush Welded, V-Flow, Raptor, ect...
Note the internals. Single deflector design lacking the Delta Flow technology which causes it to not only be loud, but can drone A LOT.
Next up and second loudest is the Flowmaster Super 44. I personally run this muffler currently as it tends to be deeper sounding then the Original 40 and Super 40 mufflers. It will give you the 40 series sound, but does not sound as "hollow". The tone is deeper while utilizing Delta Flow Technology. This means cruising drone is lessened, but not minimized fully, and gives a nice deep throaty sound. This muffler is slightly louder then the Super 40, while killing some of that drone the Original 40 has. Note the below- this muffler has 2 medium sized sound deflectors.
Next up we have the Flowmaster Super 40 series muffler. It's important to note that this muffler is used in Flowmaster's American Thunder series cat back systems. This muffler is much more true to the classic Flowmaster sound. The sound is more "hollow" while utilizing Flowmaster's Delta Flow technology. This means you get the sound of the original 40 series muffler without the ALL the drone that comes with it. What I am saying is there is still drone, but not nearly as much. Take a look at the below. You will see two medium sized deflectors followed by a single small deflector
Last, but not least, is the Flowmaster Delta Flow 40 series muffler. It's weird that's it's named this way as the top two mufflers utilize the Delta Flow technology, but this muffler takes it to the extreme, I guess you could say. This muffler is significantly quieter then all the mufflers stated above, but still gives you that signature sound when you get on it. This muffler almost kills all drone, and you will even see some people complain this muffler is too quiet. See below - this muffler utilizes a large deflector, medium deflector, then a small one.
And now you know. The next time someone complains about their 40 series muffler, ask them which 40 series exactly do they have? This could help pinpoint exactly why they hate it and now you can offer a suggestion of how they can keep their 40 series sound while keeping it at a sound level they can enjoy.
