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Old 08-24-2009 | 08:56 AM
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Default need advice on clamp -on mufflers

I need to get a couple sets of clamp on mufflers. I pulled off my Big Gibsons with the Gaffrig air pump and lines, I want some full time clamp on mufflers for 4". It honestly isnt too loud for the lake. The WP went by me several times this past weekend and never looked twice at me, a couple times I was really into the throttles.

So, I am not looking for a lot of db reduction, just something that will extend the pipes out a bit - I am concerned about water reversion, and looking to take just a slight bit of the bark the exhaust has out of it.... and something that looks really nice is a big plus.... I have looked at the full time gibsons, HPI's, etc.... any recomendations? again, not looking for big restriction or db reductions, very slight. thanks.
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Old 08-24-2009 | 10:34 AM
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Honestly one of the best looking, sounding and performing are the Sound Elimination Mufflers by CMI.

Email me at [email protected] for pricing and availability.

Mention OSO in the email please.

Kirk
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Old 08-24-2009 | 11:02 AM
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with the gafrig clamp on style with the pump actuator etc. looks like you need to drill a 11/32 hole through the transom next to the exhaust pipe for the actuator rod. is this correct?

those cmi's look nice. is there a open area on the under side of those?
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Old 08-24-2009 | 11:34 AM
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That is what I had was the Gaffrig air pump controlled clamp ons. Spring pressure held them open, but then air pressure would hold them close when you needed it. I want to get away from all that, gel the holes up and put a full time clamp on muffler on... those cmi's do look nice, but am thinking those will quiet it down a lot mroe than I want it.

I would also like somethign a little smaller and cleaner looking... Here is a pic of what I had...
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Old 08-24-2009 | 12:58 PM
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No open area below the CMI's. All the exhaust goes out the back. I just put two sets on my Pantera with 502's. They will muffle the exhaust at less than 3000 rpm and then they open to full open exhaust after that.
No flaps, no pumps and nothing to worry about. Back pressure opens the outer ring out to hang open on a cam that springs shut after you slow down. CMI tested to ZERO back pressure at WOT!
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Old 08-24-2009 | 01:17 PM
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Thanks Brad.... I really like the concept to them... I sure would like to hear what they sound like at idle though.... I guess thats the draw back here, I need to take a guess and buy something and try it, and most likely stuck with them if I dont like them.... I'm not really liking that
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Old 08-24-2009 | 02:28 PM
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I assume you are talking about reversion from wave action since you have basically dry exhaust like mine and no internal flappers. Really the only other alternative foor waht you are loking for is Drew Marine Shotguns. They are a lot less $$ than the CMI's, but don't look nearly as good. They work the same way as the CMI's.
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Old 08-24-2009 | 02:48 PM
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A guy I know has CMI's on HP500's. 90 Db at idle. Probably 98-100 without the mufflers.
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Old 08-24-2009 | 03:58 PM
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Originally Posted by Griff
I assume you are talking about reversion from wave action since you have basically dry exhaust like mine and no internal flappers. Really the only other alternative foor waht you are loking for is Drew Marine Shotguns. They are a lot less $$ than the CMI's, but don't look nearly as good. They work the same way as the CMI's.
yeah, sorry, I should have clarified.... with nothing on there now it seems easy for water to splash back up in there eassily and go down the risers.... I want to clamp something on that will provide a minimal amount of sound suppression, and also help prevent the possibility of water reversion....

I am basically looking for something like this I think:
http://www.hardin-marine.com/detail~ID~286.aspx

I just dont want to muffle the sound too much.
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Old 08-24-2009 | 03:59 PM
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Originally Posted by Gladhe8er
A guy I know has CMI's on HP500's. 90 Db at idle. Probably 98-100 without the mufflers.
Really? Interesting.... I have some mildly mod'd 502's with blowers .... I dont mind the CMI's, but am not too crazy about any moving parts.
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