Very quiet turbo exhaust - LFN sensitivity
#81
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I have a full FM setup from the manifold back. It's a 2.5 exhaust with a cat and muffler... It gets a bit loud and droney on the highway and is louder than I thought it would be.
Any advice to get it to quieten down a bit? I figured this was a good thread to ask in.
Any advice to get it to quieten down a bit? I figured this was a good thread to ask in.
#82
Summary from this thread:
1) Magnaflow muffler is the quietest muffler. Replacing current muffler with magnaflow will probably fix the issue by itself. Not really much point in doing anything else until the offending non-compliant muffler issue has been remedied. EO2K's dual flow magnaflow is even quieter than the ones most people use. Part number is in this thread, I think page 2. Look for a ton of pictures.
2) If still too loud, adding the biggest resonator you can fit will also help.
3) If still too loud, adding 2 of the biggest resonators you can fit will further help.
4) Failing that, a spring loaded flapper valve will make a significant difference with very little pressure loss (pressure loss will depend on the spring constant, so if building one yourself, keep that in mind). Jason ripped one out of a dynomax VT that worked well. I think it would be easy to make one if you have any welding and machining skilz. Can also look into the Apexi exhaust control valve; 18PSI used one with good results.
5) 1/4 wave resonator will also help at specific frequencies with zero pressure loss. While effective, it might be tricky to fit one under a Miata, especially with 2 resonators and a big *** magnaflow.
1) Magnaflow muffler is the quietest muffler. Replacing current muffler with magnaflow will probably fix the issue by itself. Not really much point in doing anything else until the offending non-compliant muffler issue has been remedied. EO2K's dual flow magnaflow is even quieter than the ones most people use. Part number is in this thread, I think page 2. Look for a ton of pictures.
2) If still too loud, adding the biggest resonator you can fit will also help.
3) If still too loud, adding 2 of the biggest resonators you can fit will further help.
4) Failing that, a spring loaded flapper valve will make a significant difference with very little pressure loss (pressure loss will depend on the spring constant, so if building one yourself, keep that in mind). Jason ripped one out of a dynomax VT that worked well. I think it would be easy to make one if you have any welding and machining skilz. Can also look into the Apexi exhaust control valve; 18PSI used one with good results.
5) 1/4 wave resonator will also help at specific frequencies with zero pressure loss. While effective, it might be tricky to fit one under a Miata, especially with 2 resonators and a big *** magnaflow.
#84
Haha, I'm glad you guys got it working!
Thanks for the data point; one thing I've learned from this investigation is that people's definition of "very quiet" varies wildly. I'm hoping the 2 ultra quiets and magnaflow will be good enough for me.
Thanks for the data point; one thing I've learned from this investigation is that people's definition of "very quiet" varies wildly. I'm hoping the 2 ultra quiets and magnaflow will be good enough for me.
Last edited by Engi-ninja; 07-21-2017 at 08:17 PM.
#86
I have a full FM setup from the manifold back. It's a 2.5 exhaust with a cat and muffler... It gets a bit loud and droney on the highway and is louder than I thought it would be.
Any advice to get it to quieten down a bit? I figured this was a good thread to ask in.
Any advice to get it to quieten down a bit? I figured this was a good thread to ask in.
I suggest selling the muffler section and building a replacement with the big Magnaflow as a first step.
#87
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I have a cat as well, which should have quietened things down as well.
Thanks for the input.
#90
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Update: MK Turbo successfully fit 2 vibrant ultra-quiet resonators and the big magnaflow muffler. The result is the most nearly silent straight through 3" exhaust you've ever heard. Concealer404 says it's quieter than a stock MSM. Will work on posting a drive by at some point.
Adding 2 resonators is not something I am going to regularly do, they don't fit in my standard boxes.
#100
I had a good one that i sent to @vteckiller2000 but i've deleted it since. Maybe he can easily come up with it? It was REALLY nice. Much impress.