Clamp on muffler or inserts
 

I have a set of new Zul blower motors with CMI through transom 4.5" tails. The water comes in through a jacketed pipe at the very end. The boat is to loud for me to take the kids out, so i am sad to say I need mufflers. I have been looking at CMI's sound eliminations clamp on's, Gibson clamp on's, Aqua Power LTD clamp on's and GGB's inserts. What experience have you had. CMI's tend to be the priciest, then Aqua's then Gibson. GGB'S are 1/3 the price of the more expensive ones. I am just not sure if they work. I also don't want it to be to quiet. I also considered the turn downs but have heard varying experiences. Any help as always is appreciated!

i personnaly wouldn't use any insert with a hi-perf big inch engine...exhaust gases need volume to expand...get the biggest clamp-on you can tolerate

I have gibsons and like them. I dont think I would do the slip in kind.

How quiet are the Gibson? What power are running and was there any loss in rpm?

GGBs are great and simple , they really killed the pounding on mine , the water is dumped right near the end on mine also I was very surprised how it tamed down without power loss .

+1 the GGB's take the bite away but still sound good. No power loss and they're cheap. Mine are 4 1/2 inch clamp ons

I don't think GGB makes clamp on's anymore, they only have the inserts listed. I am also considering the Drew Marine ones.

I'm pretty sure they still make them. I just bought mine a couple months ago. They sent me a price list of everything and they were on it

I had some Gibsons on my blower motors only 650 hp def quieted them down significantly.
Only problem was it caused me to blow 2 drives in one weekend.
Put them back on shelf! Got some headsets!!
Those damn muffler Bearings

Gibson PN# 110003, 4 1/2" clamp on. They didn't list a price.

I ordered the Drew Marine Shotguns today

We got the same problem, the water dumps at the end and it is very loud. Like you, been looking around for something to tone it down but not to much. How much do you think it will tone it down... 20 percent? Or do you think it will be more?

I had GGB clamp-on 4,5's on my old 'Gun, worked great, passed our sound test at idle. Got transom mount GGB's on the Mystique, also very please. No power loss.

Frank, FWIW my boat had a set of GGB's. The engine builder claimed there was very little (if any) loss in power/speed, but they definitely took the bark out of it. Personally, I like the bark... if others don't I typically keep ear protection on the boat, although I've yet to have anyone use it. Besides, at 96 mph all I hear is blower whine anyway! :D

With the kids I agree toning it down a notch might be a good idea though.

I visited Lake George so I put a set of Aqua power clamp on mufflers. They make a 525EFI barely legal at 90 db. If the test is not done correctly it fails. I was thinking of adding a small GGB slip in if I ever go back. But on the other hand I might never go back, sorry that's for a different thread. Doug

They claim 10-13db. I am not worried about a ticket as much as the kids. I figure if it takes the bark out at idle and slow cruise I will be happy. I will update this thread next week. I was going to buy the Aqua Power clamp ons, but did not want to wait and did not want it to quiet. The boat had mufflers last year it sounded like a chevy Citation. Biggus I hear everyone talk about the GGB's but they only list the inserts on their site.

I just bought a pair of the GGB clamp on's
But have not put them on my boat yet. I have Zul
Engines myself and they are loud, I do have boat up for sale
and trying to work a deal on a new boat, if I don't use them
I will sell the clamp on's.

That's exactly how I feel, not to much but we would like to hear the radio at 35 mph.

mufflers
 

How did the mufflers work out ????????????????