Question about dry exhaust???
02-09-2007, 05:40 AM
#11
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Re: Question about dry exhaust???
I have a set s/m dry and have a 1'' bypass and small exit out the top end of the pipes every loud 670hp
. I just stay offshore and out of harbors
. I just stay offshore and out of harbors
02-09-2007, 09:45 AM
#12
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Re: Question about dry exhaust???
The thermostat outlets on standard cooling are 1". All the water goes through those before exiting the exhaust. Those 1" exhaust outlets are adequate to handle the waterflow.
I've had dry, they are loud! If you add clamp on mufflers, consider dumping some water just prior to the mufflers. Some dry exhausts already have a small hole at the inside back bottom that does this as well as allowing the pipe to drain after shutoff. The water will quiet it down and may prevent discoloration of the mufflers.
I've had dry, they are loud! If you add clamp on mufflers, consider dumping some water just prior to the mufflers. Some dry exhausts already have a small hole at the inside back bottom that does this as well as allowing the pipe to drain after shutoff. The water will quiet it down and may prevent discoloration of the mufflers.
02-09-2007, 10:35 AM
#14
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Re: Question about dry exhaust???
1" exits are fine, and you can always make them bigger. If you don’t have a water pressure gauge, get one and keep the pressure below 25psi. My Stellings have 1" exits, and with 1000+HP I had no issue with flow.
Unless you have a canopied cockpit the noise is just too much. I'm talking serious hearing loss. One ride with no mufflers on mine made my ears ring for hours. Now I dump water at the tips into mufflers, and it just stays legal at idle. But its plenty loud on plane.
Unless you have a canopied cockpit the noise is just too much. I'm talking serious hearing loss. One ride with no mufflers on mine made my ears ring for hours. Now I dump water at the tips into mufflers, and it just stays legal at idle. But its plenty loud on plane.
02-09-2007, 11:11 AM
#16
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Re: Question about dry exhaust???
I run full dry CMI headers and pipes. The water and exhaust doesnt mix at all. The water dumps out of bungs ( I guess about 1" or so ) welded to the tails and thru the transom by a thru hull fitting. I have no by-pass valves nor do I have any pressure problems. Much like your 525's, I run closed cooling. The down side, they were very loud, too loud. At the time, GGB was still around. I got a set of their Extreme mufflers. They made a big difference. Its still loud, but its bareable. The best part, no power loss at all after adding the mufflers. Too bad they are out of business. 
It was fun for a few months, but gets old. No one wants to run behind you and the folks at restaurants on LKN were complaining.
The mufflers really do take the edge off, and it is still much louder then stock.
I have ran water pressure gauges for years and there was no change in pressure from stock to the drive set up on our boat.
Last edited by Dock Holiday; 02-09-2007 at 11:13 AM.
02-09-2007, 11:36 AM
#17
Re: Question about dry exhaust???
I hope I haven't made a mistake by going dry. I was just sick of having the quietest boat out on the lake...most single engines were louder than my twin engine. No joke, people used to say "here comes the quiet boat" or "hey why don't you start that thing" when it was already running. I guess if it is too loud I can always slip in the mufflers but then I am back to square one and out $2500. Is it really that loud? I'm a little concerned now since I don't have a swim step to cover the exhaust, it just hangs out there. My wife is going to kick my ass if it is too loud.
02-09-2007, 01:36 PM
#20
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