Muffler Recommendations
 

Does anyone have any first-hand experience with mufflers they can share? Looking to ditch my Corsa silent choice and go with something simple at the transom. Either clamp on or thru-bolt. Thanks.

I had these imco's on my boat, they actually turned the diesel drone into more of a growl and sounded better but still louder than I wanted so I tried the Gibson clamp ons which are slightly more restrictive but quieter. The diesels just don't have a good sound so I quiet is good but with a V-8 it is still nice to hear them a little. I have the IMCO's in the swap shop if you are interested.

http://www.offshoreonly.com/forums/s...p-muffler.html

I saw your post and unfortunately, those are waaay too long for my application. I need something 12" or less.

Thanks for the reply.

What about the teague switchable like the ones on the 500efi. St-450 I believe. I have them on my boat and love them

These are what I have now they should work for you.

Gibson Performance

I bought GGB inserts
4" - GGB Exhaust Technologies
Clean (reversable) installation. Can't comment on the sound yet though (a few more weeks before splash)..

I have two Gibson 4" thru transom mufflers brand new never used I will sell to you for $250.00 shipped in the US.
They are somewhere around $350 new, I bought them and they would not fit my boat because of the intergrated swim platform. I could have modified them but opted for another route.
New still in the box with all paperwork, and they won't hang out the back of your boat.
Gibson part number 310004, can send you pics if interested.

Ron

I have Gibson clamp on and they work great, I haven't noticed any loss in performance and I'm running just shy of 700hp. The nice thing is that when I'm inland I run them and I can take them off on the big lake. I've had them several years now, they don't stay clean long though. They do keep me legal and I don't get too much static from the LEO's.

I checked those out and they're rated under 500hp. Unfortunately, I don't think they'll work for me.

4" GGB inserts
 

What length insert did you use, and how did you like the sound. Any performance change?

im not trying to make anyone upset, but i have Gibson slip on mufflers and they slow my boat down 3mph. i have a htm ss24 with a 565 n/a and with out the mufflers the boat runs 101mph on gps when i slip on the Gibson mufflers the boat will only run 98mph gps. every time, its very consistant. but the noise is considerably lower. just my 2 cents, the runs were on the same day with temps the same.

I got the 5.5" sport. They sound good, deep rumble.
I had too many changes done this year to comment on the performance (need more prop with the -2 IMCO lower). The boat is not slower than last year though.

Since loosing a GGB and putting gibsons on my 1000 ish hp boat I have lost rpms and mph, might pull them off at hot boat to see if its actually the problem, Smitty
The good GGB'S ran same exact mph and rpms open vs with them on a few years go and I was running 99 mph at the time FWIW

Go with imco gattlins. Takes out the bark, leaves a deep growl and no performance loss. Highly recommended.

What are ggbs, the actual name to look it up

I guess it is these...

https://www.wr-products.com/pages/ggb-marine-exhaust ggb actual website... GGB Exhaust - Power by Design? looks like dealers only website.

Okay thank you for the information but those are all insets for the pipes-mufflers.Where are the mufflers for sale?

I think the idea s to not have an added on piece hanging off the back. do you have a straight shot you can slide an insert up the tailpipe? (sounds dirty!) or any hose sections inside boat between engine and tips? and are your exhausts wet or dry ? I only see inserts for sale, but this youtube video they are installing a muffler with case in the exhaust path inside. so they must be available somewhere. you could also buy stainless tubing and put inserts in and mount them the same way. I wouldn't want to do something like that to add on outside the boat though.