I've decided to get some mufflers. My boat has open exhaust and it is just too loud at idle to have a normal conversation.

I've checked out all the muffler threads in the Q&A section.

Here's the choices that I like.

GGB Extreme's. Open muffler. Good sound reduction all the time. Advertised as no power loss. Clamp on available.

CMI's new muffler. This has a spring loaded baffle on it that makes it run quite until exhaust back pressure opens the baffle at approximately 1/2 throttle. Maybe quieter than GGB's at idle and louder than GGB when running. Clamp on available.

Teague's ST-450 electrically switchable exhaust. Same concept as the CMI but has a switch on the dash to choose whether opened or closed. This has the neato factor, but I don't know if it would be good to run them closed at high rpm anyway and they would be the hardest to install.

Anyone with some experience care to offer their opinion? I'm tempted to get the CMI's because I don't think the boat is too loud once underway. It only bugs me at idle when I'm trying to talk.

Thanks,
Garrett

I find myself in a similar situation after removing my silent thunder and going with Livorsi 4" exhaust tips. Saved about 75lbs of fiberglass

Anyone have any before and after sound clips from their muffler set up? Any input on the new CMI's?

Jamal

Definatley go with the GGB's I have the thru transom version on my formula, And it did reduce the db's to around 87 on my 502's no rpm loss

Garrett,

The switchable mufflers are not legal at most of the lakes...has to be something that can't be swithced on the fly.

I just installed some new mufflers from Precision Marine (Huntington Beach) they work great no power loss.

KL

Garrett,

Just installing the GGB Extreme clamp-ons on mine. Won't know results for about another month.

Where did you find info on CMI's new muffler? I was @ their website and did not see anything about a spring loaded muffler. I too want to remove the silent thunder & go with some mufflers. I would like to find a muffler that is quiet at idlle but gets louder with higher rpm. Did you give the drew marine shotgun muffler consideration? The march 2005 hotboat has a test of 22 clamp ons that I dug out of my archives last night. Thanks

i installed the ggb thru hulls on my 302 with superchargers, it cut the noise down huge. now it has a awsome tollerable sound.

Trick Marine has them.

I'd like to do the clamp on GGB's but I only have 1" of tailpipe and the info I have says they need 2 1/2 inches. I'm not sure how difficult it will be to install the transom mount. Anyone done it?

Thanks,
Garrett

Rippem put two sets of Corsa's on his 353 last year and they are transom mounts. I have the same Corsa's on my 353 and I think they sound pretty good. I'm looking forward to see how they will sound with my new CMI elbow tops!

Dave