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A quiet axle back?


TMO Intermediate
As of now I'm running Catless Longtubes, magnaflow Resonator with Roush Axle backs and even with the resonator, it's terribly obnoxious. They Roush mufflers were great until I added the LT's but now it's so high pitched and ear piercing there's no way I could comfortably race it on track or drive it on the roads. I have a Pleab car so no active exhaust with valves and honestly I don't want the headache. There's so much bad information on sound levels I knew this would be the place to ask.

*The sticky thread here seems more about the active GT350 exhaust.


TMO Addict
Borla Tourings also are straight through but fairly quiet while still sounding deep. Borla guarantees no drone, too.


TMO Intermediate
Check out the Corsa Axle Back , likely your best bet as their main technological focus was eliminating drone, while giving a strong throaty sound under power or cold start up.
I also agree with this, having the Corsa system myself. Their RSC-equipped (reflective sound cancellation) mufflers use a naturally-occurring audio trick called destructive phase in order to negate the sound waves when under cruise (~2000 rpm) conditions. The muffler has pathways in it that sample the exhaust wavelengths and are tuned to reflect them back 180 degrees out of the original phase (peaks in valleys and valleys in peak on the waveform).

This allows the sampled-and-reflected waveform to cancel out the exhaust waveform WHEN they match frequency (albeit, at opposite phase) and only at cruise (won't effect idle). If you dip into the throttle, they won't match and won't cancel each other out. It's ingenious, really. Constructive phase (as opposed to destructive) uses two identical waveforms that are in phase, making the sound louder. (It's a technique we use in video/audio editing when the original audio track is too soft and we need to boost the levels organically without also raising the sound floor using typical 'gain' controls)

Hopefully this diagram helps explain it a lot easier:

Now, there are other restriction and reflection moments in a normal exhaust set up as well that affect the exhaust's note. You'll see plenty of people with Corsa exhausts online that, in my opinion, just sound absolutely horrid (mostly because they use catless long tubes and then just straight pipe it back to the mufflers). It's noise rather than sound. Your longtubes without cats will change the sound, since there are different dampening and reflective events happening. Additionally, any change to resonators (or the lack there of) will have an effect. I think resonators play a large part in the refinement of an exhaust system's note, if that's what you're looking for. Corsa has different levels of exhaust, so you may find that returning to the stock resonators and using a 'Sport' sound level rather than a 'Xtreme' sound level with your catless longtubes may actually give you the result you're looking for. If you decide the Corsa system sounds like something you want to look further into, I'd suggest having a conversation with one of their reps regarding your application and desired outcome.


TMO Intermediate
I don't want loud, I have lost enough hearing as it is. Is there such a thing as a quiet but very low restriction muffler that doesn't weigh a ton(ne)? I mean like OEM quiet.
I'd suggest calling Corsa and asking about their Touring sound level. I'll post their blurb below describing the sound levels they offer. If you do that and put the stock resonators back in place, you may be able to hear your door chime afterwards haha.

"CORSA Exhaust offers 3 levels of sound: XTREME - their loudest offering for those who want the loudest baddest sounding system out there with an aggressive tone, CORSA's SPORT systems for their mid sound level is a great alternative for customers who want an aggressive sounding unique exhaust but who do not necessarily want to hear it all the time. The sport option is a good option for mildly modified vehicles and for comfortable highway cruising, CORSA's TOURING exhaust is their quietest system for those with highly modified engines or those who wish to only have a slightly louder tone then stock. No matter your sound preference, CORSA mufflers have you covered."


TMO Intermediate
Magnaflow mufflers are generally pretty quiet while still maintaining good flow and low weight. I've run them on my last few cars and currently am using RTR axlebacks (Magnaflow streets with a different inlet) and love the way it sounds. They eliminate the robotic wub-wub sound most coyotes have.

Looks like they offer them for the S550 too:


TMO Advanced
There’s also these mufflers, been curious about them for a while. Maybe someone has experience with them. I’m going to be making the (hopefully) quietest high flow exhaust I can and at least theoretically this seems like a good contender



TMO Intermediate
I too have settled on the Borla Touring. My car is a 3V, so a different sound, but it has cams which seem to make it very loud compared to stock. I tried stock mufflers (less performance, but quiet), FRPP FR500S mufflers (really loud with the cats, and ear splitting without) and finally settled on the Borla Touring. Not quiet, but tolerable for my neighbors even without the cats as I leave for the track at 5:30 am. So either my neighbors are just being nice, or they aren't being woken up by them.

Bill Pemberton

0ld Ford Automotive Racing Terror
Blair, Nebraska
W2W Racing
20+ Years
JDee, the Corsa is the State of the Art to reduce drone, and frankly it is throaty under full power , but not obnoxious. We put over 500 systems on Vipers and we had access to everything else ( Borla did the MoPar catback ) and nothing met their tone to cruise, drive around town, and even not be annoying on track. We had plenty of Challengers running Magnaflows and they were fairly decent , but the bulk of the systems out there are a constant ringing in the ears. Follow the advice of our new Member in Maryland and go with the Touring Corsa.

It is amazing how many don't get the Corsa initially because it is a little more costly and then bingo they get switched out. I remember at least three guys who yanked he system off their Boss 302s after they heard the one on my 2012 Comp Orange , years back.

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