Mazda 6 MPS - Exhaust Muffler and Resonators?

[kh92]

I've searched everywhere and did read some stuff up, but most of the stuff is about Mazda 3 MPS.

I apologize for asking something that must've been asked so many times already, but...

On the Mazda 6 MPS, how many mufflers are there? Is it just then two at the end before the exhaust tips?

And what are resonators? Apparently "hotdog" looking things before the muffler... I have seen no such thing.

Reason I'm asking is that I want to modify my stock exhaust for a deeper note / sound / noise

What's the best way to do this? Removing mufflers and replacing with straight pipes or what etc.

Thanks in advance!

[Toddy22587]

Its been a while since i've seen a stock exhaust on an MPS so i might get this wrong. Stock exhaust has 1x cat right after the turbo, another cat at the end of the downpipe, then at the back it splits into 2x mufflers.

If you want to modify the exhaust purely for sound and not power then i would suggest replacing the 2 rear mufflers with a straight through design muffler. any decent exhaust shop should be able to sort that out, no real need to buy a prefabricated item

[kh92]

Thanks
What about these "hotdog" looking resonators?

[Toddy22587]

They aren't really mufflers. In my system i have 1x cat after the turbo then it goes through a resonator "hotdog", then splits into 2x straight through mufflers. The resonator helps to reduce the noise / drone without restricting the flow of the system

[kh92]

So therefore removing a resonator would increase noise level? Just want to make my stock exhaust louder as I can't afford a TBE right now lol
Any idea how to remove the resonators? Or will exhaust shops do this aswell as straight through mufflers?

[Toddy22587]

cant remember if there were any resonators in the stock system. the main thing keeping your exhaust quiet is the design of the rear mufflers so if you replace them with straight through mufflers you should get a major increase in volume

[andy b]

I don't think the 6 has a resonator.

If you can't afford a turbo-back system yet, why not go for a cat-back which will still bolt up to most aftermarket downpipes if you choose to go that way later on, or just have your rear mufflers replaced as Toddy suggested. I looked into it and had a quote of about $280 for Lukey mufflers

[Nuliaj]

[kmh001]

[QUOTE=kh92;178848]
And what are resonators? Apparently "hotdog" looking things before the muffler... I have seen no such thing.

[QUOTE]

Resonators are what people use to reduce the flow rate of an aftermarket exhaust to less than that of the stock exhaust (that's tongue in cheek, but I'm also suggesting it's true). And unfortunately the 6MPS doesn't lend itself to simple exhaust mods that give you a little bit of extra noise but not too much. The gen1 3MPS is much easier to mod in this way.

I fear that you're about to spend a heap of money on mufflers. Then you'll find the droning is impossible to live with. So you'll spend more money adding a resonator. Then your exhaust will be more restrictive than the stock exhaust was. Most guys who go down this path either don't know or don't want to admit they've spent a heap of money and gone backwards.

Disclaimer: the R&D quoted below was done on a car with a modified down pipe so the same results may not be fully realised on a car with a stock DP.

Here's my suggestion for a cost effective and efficient alternative:
The stock 6MPS mufflers have excellent flow and sound characteristics. This has been proven on a dyno by a degree qualified engineer - bear that in mind if a salesman with no engineering qualifications tries to sell you a droney exhaust. The same engineer also demonstrated that the only significant flow restriction after the cats in the 6MPS exhaust is the T piece. So when you buy a super expensive after market exhaust the only part of it that's doing you any good is the improved T piece. And if that super expensive after market exhaust is larger than 2.5 inches it's probably doing more harm than good. That's because the enigineers R&D also found the 6MPS made more power with a 2.5 inch mid pipe than it did with a 3 inch mid pipe. I love it when objective evidence dispells the usual assumptions. So the optimal exhaust mod on a 6MPS is a 2.5 inch mid pipe (number 4 in the above diagram) with a nicely contoured T piece using a merge collector that gently steps down to meet the stock mufflers. This shoud cost less than $500, it will have no drone and will almost certainly give you more power than any after market exhaust that has a resonator added to reduce the inevitable drone. I haven't got around to doing this mod yet so unfortunately I can't tell you how it sounds. But if you wait a few weeks I'll let you know.

[Nuliaj]

But don't forget kmh, his main reason for doing this is for sound not performance. One of the better sounding exhausts I've heard on an MPS6 was on a ex-member's car that had a 2nd cat delete, custom 2.5 down to dual (massive) Fujitsubo mufflers. I can't recall if it had a resonator or not, but there was no discernable droning throughout the rev range.