3227 Exhaust Noise

yhtguy

Member
Joined
Mar 1, 2013
RO Number
33179
Messages
19
I am trying to figure out a way to quiet down the exhaust on my 1990 3227 with 305 Crusaders. I run the boat a lot at about 7 knots (1200-1400 RPM) do to speed limit requirements on the lake I am on. The drown from the exhaust is very annoying while running from the flybridge. The noise overall is pretty aloud.

I am wondering what other 3227 and even 3207 owners experience?

I have tried researching other muffler systems and turndowns.

Any thoughts, comments, advice???

Here is a picture of my engine room showing my current setup. Picture was taken when I had the deck removed while buying the boat.

IMG_1068.jpg
 
Not enough muffler. I was in th e ER of a boat like BillyIII a week ago. It had HUGE Vernalift mufflers. Very, very quiet. Depending on the configuration, if you could attach elbows that will push the exhaust underwater will help. I believe Rommer did this with his last Regal.
 
Mine has a similar setup but I don't think that it loud on the bridge. It is loud for people below or behind me but I like the way it sounds.
Jim
 
I had thru-hull exhausts on my 3297 Mariner wither Crusader 350's. Yes it was loud at idle or low speeds, but at planing speed, it was relatively quiet as most of the noise was behind the boat. My Mariner had much larger mufflers and was still loud so I don't think a larger muffler will solve the problem. I've seen an elbow that attaches to the thru-hull fittings that direct the exhaust underwater at anything less than planing speeds and they are much quieter. The other alternative is to switch to waterlift mufflers. The caveat there is to make sure the engineering is right so you don't get water ingestion due to improper setup. Centak muffler customer service can probably assist you there.
 
I don't remember the 3227 having that style of muffler. Carver usually used a canister muffler that was upright and would fill with water while the engine was running causing it to quiet down. That may not be the factory set-up and may have been done to "save some money" as opposed to replacing with the correct system. The original mufflers would have been attached to those plywood boards directly aft of the engines. Try "Marine Muffler" for different types of mufflers that may work.
 
Mufflers ? Try 2 454's without any...that's loud. My 3607 doesn't have any.
 
The "mufflers" on those engines are worthless. There is plenty of room to fit mufflers that will solve your problem.

My last boat had 454's with "mufflers" smaller than that, I loved the way it sounded!
 
seems that you have several choices. Below water exhausts if they still exist., vertical mufflers or much larger horizontal mufflers installed crosswise so that the exhaust exits on the opposite sides.
 
I have the same set up. It too is loud at those speeds. I turned my outlets at a 45 and it hekped.a.little. its not lous enough to be concerned with doing more. These are stock factory mufflers. Honestly coming from owning bb chevys in an offshore sunsation....this is quiet lol
 
Sorry about my typing from this phone. Its a pain in the ass. Questjon tgoufh. How do those 305 push the boat? I honestly am debating upping my hp for a faster cruise
 
Ken34 - I am happy with the performance and economy of the 305s. I run the boat at 3000-3200rpm and get 16-19 knots. I've even seen 21 knots with a nice current behind me. I've put 80 hours on the boat and have figured I'm burning about 17-19 gph at those RPMs.

I used to own a Crusiers 3470 with 7.4 MPIs. I would run it at about the same RPMs and would see 18-20 knots burning about 22-25 gph.

Where did you find your turndowns? i have been thinking about doing the same thing.
 
Those are pretty fair numbers. Ultimately I would like a set of sbc mpi. I think that would fit the bill.
As for the exhaust. I have stock round flaps that were facing straight down. I took them and rotated them so the angled more towaed the outside. This pushes more noise away from the transom by elleviating the bass effect caused under the platform. I hope that make sensse. I will try to remember a pic next time I am at the harbor.
 
By the way, the exhaust look like the half basketballs on the back of the transom...if that makes sense!
 
I have no mufflers on my 454's....
There are simple abs pipe turndowns at my exhaust thru-hulls that go down past the waterline under the swim platform. Works great.
 
quote:

Originally posted by Ken34

By the way, the exhaust look like the half basketballs on the back of the transom...if that makes sense!






I forget who makes them and couldn't find them online so here is the HomeDepotLowes Version on a go fast.

PVC.jpg


WWII PT Boats used them as well.

03Mufflers.jpg


What ever works!
 
Mine is just like the first example, except in 2" black abs, with 45 deg elbows, and flare cuts on the trailing edge of the straight lengths going down into water
 
because the hot manifold may create a vacuum when it cools and suck in water. It may not be very likely but who knows??
 
Here's an example of how my exhaust is plumbed with the turn-downs I described.
Hope this helps, I've found it pretty effective.

IMG_0525_zps94ea23e9.jpg
 
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