454 thru-transum (muffler?)
 

Hello,

Got pulled over this weekend because of noise. I have to go to the Sheriff dept to get a decibel test. I won't pass. Does anyone know about a muffler I can put on my boat and that won't totally kill performance?

Thanks,



Tom

Re: 454 thru-transum (muffler?)
 

Where did you get stopped?

Re: 454 thru-transum (muffler?)
 

Lake Minnetonka, Mpls, MN. Near a channel.

Re: 454 thru-transum (muffler?)
 

Last year I had stock Merc exhaust with 12" long slip in baffles. They wewre the glaspack type, no plate to force the exhaust to divert. Just a slight restriction to get some to divert. When I removed them, I lost 25 pms. Stock exhaust like a little backpreasure. I think IMCO makes one very similar.
This year I went to Gils and gain 50rpms, no baffles. And, the sound is better than the stock with no baffles. Maybe a little quieter but deeper and less anoying.

Re: 454 thru-transum (muffler?)
 

On my last boat I had a sb in it my wife hated it I put some slip on muffs from cpperformance and it seemed to tone down the noise. I don`t remember a gain or lose in rpm`s.


Hope this helps

mark

Re: 454 thru-transum (muffler?)
 

I apologize for cross posting here, but right now there is a good thread going on the Classic Donzi Registry about what you are asking about. Don't mean to offend anyone here, just trying to help.

Re: 454 thru-transum (muffler?)
 

check out this thread here:

http://www.offshoreonly.com/forums/s...ad.php?t=82410

Re: 454 thru-transum (muffler?)
 

Thanks for the info everyone! I found the other threads and learned a TON! I've narrowed it down to a couple ideas that I'm considering. Thanks! I'll post the db results after I've installed a solution and had it measured by the Sherrif.

Re: 454 thru-transum (muffler?)
 

For your test, maybe you can kick the water flow up. Water is a excellent muffler and flowing some extra water into the exhaust could be the magic ticket to passing. Some people also make up "donkey dicks" These are pvc pipes that attach to the existing tips and direct the exhaust below the water line when you are off plane. Most tests and the laws are directed at the idle test, so these are very legal. With a wet exhaust they stand up pretty well too.

With the mufflers, it's tough to separate the bs from the facts. I'm signing up for a set really soon and I'd be happy to report back on the results. It won't be for a couple of weeks though.