Boat Mufflers
03-11-2008, 12:25 PM
#3
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According to what link I found, the 2005 law varies from state to state (see below)
Using the SAE J-2005 (stationary test), most states set maximum noise levels at 86 to 90 dB. When the SAE J-1970 (shoreline test) is used, the maximum noise level is commonly 75 dB.
Also add in the variable of what many mufflers use as a sound deadner, water. The amount (or lack of) that your exhaust emits will either enhance or inhibit your marine muffler. Suggestion: Go with a proven product. My choice is the Gibson product line. Hope this helps.
Using the SAE J-2005 (stationary test), most states set maximum noise levels at 86 to 90 dB. When the SAE J-1970 (shoreline test) is used, the maximum noise level is commonly 75 dB.
Also add in the variable of what many mufflers use as a sound deadner, water. The amount (or lack of) that your exhaust emits will either enhance or inhibit your marine muffler. Suggestion: Go with a proven product. My choice is the Gibson product line. Hope this helps.
03-11-2008, 12:33 PM
#4
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Thread Starter
Thanks guys, I'm running 4.5" cmi dry to the last 1/2" on blown 509's. Last run was ticketed for 102db at idle so I need to drop 12db to come into compliance.
03-11-2008, 04:36 PM
#5
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Join Date: Jul 2006
Location: Seabrook, Tx
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Check out the ugly boat thread, here is your answer
http://www.offshoreonly.com/forums/s...d.php?t=181838
http://www.offshoreonly.com/forums/s...d.php?t=181838
VIP Member
03-12-2008, 12:30 AM
#8
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Thread Starter
You just need to mellow the bark. To get under the limit you need turndowns. We will test Tom Temples boat soon, he now has the CMI Sound Elimination and we measured him last year so we can use him as the baseline. He was as load or louder than you.
You know how to reach me!!
Kirk
You know how to reach me!!
Kirk
03-12-2008, 11:00 AM
#9
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Both of my cats are 83 db at idle with turndowns. This year may be a problem with all the noise issues being brought up. Once up on plane my boat is still loud. The sherrif has a hard time with a drive by test. My guess is they will go after the loud boats at idle this year for sure. That will be a good start. But who knows? I am looking into mufflers along with downturns to become stealthy. The CMI sound elmination mufflers work real well. I had them on two boats, the last boat had twin 600hp and it was legal. The really nice part about those mufflers is you can back off the throttle and they close up nice an quiet. Cruise legal. Over 3000 rpm they open automatically.
