100 Dba
 

Just took a reading and i'm at 100 Dba with my open exhaust. Currently I am looking at the following (3) systems:

Eddie Marine switchable - Replaces existing tips

Rex Marine switchable - Replaces existing tips

Drew Marine automatic - Bolt on

They all claim anywhere from 10 - 14 Dba reduction at idle, which gets me legal. Out of the three, which is the recommended?

I don't have any of those systems that you mentioned. I do have experience with the Teague system though. I don't know if you have considered them or not, but the pricing is quite attractive.

I have Shotguns and like them, but I doubt they will get you quiet enough to be legal if you're at 100db. Thats pretty LOUD for a single. Did you take an ambient noise reading prior to the 100db reading???

How far away from the boat are you taking your readings from?

My shotguns only dropped me from 96 to 92. Which is really a lot. I would wonder about any 10 db claims in the 100 territory. I assume your running dry pipes.

Pantera 24,

This will sound cheesy, but it worked really well for a friend of mine.

He went to Home Depot and bought some 4 inch PVC pipes and fittings for a total of $30 for 2 engines. Not the heavy weight schedule 40, but the lighter weight pipe. He had a 45 degree bend and 6 inches of pipe on one end that slid over the tail pipe. He slit the pipe a couple of times and put a hose clamp on to hold it to the tail pipe. He then put another couple of inches of pipe on the back of the fitting and attached his exhaust flapper to that pipe. The end of the pipe has to be below the water when the boat is at idle. He said all he heard was bubbles and the water swirling behind the boat. He can also remove them in just a few minutes (4 hose clamps). No performance difference noticed.

I am going to build a couple. If they work well I will use them as templates and send them to CMI or some other exhause company to make out of metal.

Steve

I took the reading after zeroing the gauge for ambient noise.

I took the reading 3' up and 3 back form the exhaust.

I'm running wet pipes.

The piping you described sounds like it would work, I would assume the DNR would know what I was doing.

I'm trying some Drew Marine Shotguns Friday, I'll post the results.

Kirk

Take a look at some transom shots of boat picks. I have seen many people do this. I know of several people in MI that have done this, Mr Gadgets friend Steve H. comes to mind. Cheap and effective. I have Teague Switchables, I went from 95 to 89 ish. I would recomend them in a heart beat. BUT when they outlaw switchables I will go the pipe route.

You won't make it with shotguns. They'll only drop it a couple of dbs.

Kirk,

I'm using Teague switchables. They recommend running up to 3000 rpm closed. Was that you at West Marine last Sunday?

Mark