Shkreet Car Interior Deshibul Levelsh
07-03-2018, 04:01 PM
#1
Shkreet Car Interior Deshibul Levelsh
Fighting a problem in my street car build.
It's OBSCENELY loud inside at the normal BP "node" RPM points. ~1500 and again in the 3000-4500rpm range. We're talking 115-120db.
Exhaust is RB front to back. Header, midpipe, Power Pulse muffler. Vteckiller measured decibels on a phone app, so take the actual numbers with a grain of salt. The frequencies that are strongest are at nodes that we would have expected the HUGE resonator in the RB midpipe to cancel. Rubber hangers.
We initially chalked most of it up to the header and oil pan contacting the subframe due to motor mount issues. I swapped mounts since then and have miles of clearance, but the interior volume level is still completely out of control. Car has no soft top, hard top is bolted on with brackets, not latches.
Anyone else running this same exhaust setup that could ballpark decibel level for me? Any similar experiences fighting noise? Car is pretty subtle outside, the interior drone is just horrid. I had a similar issue with a full FM exhaust on our original MSM. Whisper quiet outside, horrendous headache-inducing drone inside, though wasn't quite as bad as this car.
It's OBSCENELY loud inside at the normal BP "node" RPM points. ~1500 and again in the 3000-4500rpm range. We're talking 115-120db.
Exhaust is RB front to back. Header, midpipe, Power Pulse muffler. Vteckiller measured decibels on a phone app, so take the actual numbers with a grain of salt. The frequencies that are strongest are at nodes that we would have expected the HUGE resonator in the RB midpipe to cancel. Rubber hangers.
We initially chalked most of it up to the header and oil pan contacting the subframe due to motor mount issues. I swapped mounts since then and have miles of clearance, but the interior volume level is still completely out of control. Car has no soft top, hard top is bolted on with brackets, not latches.
Anyone else running this same exhaust setup that could ballpark decibel level for me? Any similar experiences fighting noise? Car is pretty subtle outside, the interior drone is just horrid. I had a similar issue with a full FM exhaust on our original MSM. Whisper quiet outside, horrendous headache-inducing drone inside, though wasn't quite as bad as this car.
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07-03-2018, 04:39 PM
#3
Fighting a problem in my street car build.
It's OBSCENELY loud inside at the normal BP "node" RPM points. ~1500 and again in the 3000-4500rpm range. We're talking 115-120db.
Exhaust is RB front to back. Header, midpipe, Power Pulse muffler. Vteckiller measured decibels on a phone app, so take the actual numbers with a grain of salt. The frequencies that are strongest are at nodes that we would have expected the HUGE resonator in the RB midpipe to cancel. Rubber hangers.
We initially chalked most of it up to the header and oil pan contacting the subframe due to motor mount issues. I swapped mounts since then and have miles of clearance, but the interior volume level is still completely out of control. Car has no soft top, hard top is bolted on with brackets, not latches.
Anyone else running this same exhaust setup that could ballpark decibel level for me? Any similar experiences fighting noise? Car is pretty subtle outside, the interior drone is just horrid. I had a similar issue with a full FM exhaust on our original MSM. Whisper quiet outside, horrendous headache-inducing drone inside, though wasn't quite as bad as this car.
It's OBSCENELY loud inside at the normal BP "node" RPM points. ~1500 and again in the 3000-4500rpm range. We're talking 115-120db.
Exhaust is RB front to back. Header, midpipe, Power Pulse muffler. Vteckiller measured decibels on a phone app, so take the actual numbers with a grain of salt. The frequencies that are strongest are at nodes that we would have expected the HUGE resonator in the RB midpipe to cancel. Rubber hangers.
We initially chalked most of it up to the header and oil pan contacting the subframe due to motor mount issues. I swapped mounts since then and have miles of clearance, but the interior volume level is still completely out of control. Car has no soft top, hard top is bolted on with brackets, not latches.
Anyone else running this same exhaust setup that could ballpark decibel level for me? Any similar experiences fighting noise? Car is pretty subtle outside, the interior drone is just horrid. I had a similar issue with a full FM exhaust on our original MSM. Whisper quiet outside, horrendous headache-inducing drone inside, though wasn't quite as bad as this car.
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07-03-2018, 04:42 PM
#5
Decibels, not vibrations. Why is this so haaaaarrrrrrdddd?
This is an exhaust drone issue i/we am/are reasonably sure. I can put stock engine mounts in it, but i've swapped engine mounts enough times in the last month or so that i'd rather shut my nether regions in a door than do it twice more.
This is an exhaust drone issue i/we am/are reasonably sure. I can put stock engine mounts in it, but i've swapped engine mounts enough times in the last month or so that i'd rather shut my nether regions in a door than do it twice more.
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07-03-2018, 04:53 PM
#8
Newb
Join Date: Jun 2018
Posts: 4
Total Cats: 0
hmm. On my naturally aspired 1.8NA, I've got jr header --> stock cat --> non-resonated rb sport midpipe --> single power pulse muffler. Mazda comp motor mounts if it matters. It's quiet. I've also had a resonated test pipe instead of the stock cat and the car was still quiet..like stock car quiet.
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07-03-2018, 05:14 PM
#13
Now you're backtracking and being confusing. You said you've driven many RB cars and didn't experience this. The car is super quiet outside and sounds great.
I'm after hard data measured unscientifically with phone apps, as well as anecdotes with similar systems. You have the anecdotes and say it was quiet and good. Got it, will put in spreadsheet. <3
I'm after hard data measured unscientifically with phone apps, as well as anecdotes with similar systems. You have the anecdotes and say it was quiet and good. Got it, will put in spreadsheet. <3
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07-03-2018, 05:21 PM
#18
I think we're still confused. I don't have a single issue with exterior volume. It's QUIET (easily as quiet as the MSM was outside). I don't have a single issue with the KIND of noise it makes, it sounds GREAT. Zero fart and gross **** you normally associate with a catless car.
My ONLY issue is with interior drone/decibel level. The noise i hear inside is a good noise, there's just WAAYYYYYYY too much of it. Got me, sugar?
My ONLY issue is with interior drone/decibel level. The noise i hear inside is a good noise, there's just WAAYYYYYYY too much of it. Got me, sugar?
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