Exhuast through the transom below the water line?
03-02-2007, 03:35 PM
#11
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I had this exact setup on my boat. It used to be at the top of the transom but you need 14" of drop so you don't get reversion so we relocated through mid transom. The exhaust gas just "knips" at the waterline, it is very cool, it is not actually submursed with thru-transom exhause tips. With external mufflers (Gibson) they were completly underwater at idle, once on plane, they were above the water.
I took the mufflers off because I hated the way it looked, performance was fine either way
Gregg Reichman
I took the mufflers off because I hated the way it looked, performance was fine either way
Gregg Reichman
04-08-2007, 08:27 PM
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The tails came from CMi and I just cut the transom holes. I will take a few pictures Monday. I think this is going to work real nicely. Exhaust should be 4" below the waterline at idle.
04-08-2007, 08:55 PM
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Notice the angle of the tails. Standard Sweep CMI headers and it works perfect for the tailpipes. Just waiting the transom tips that will be down turned and with baffles (water flaps for reversion)
Last edited by Brad Zastrow; 04-08-2007 at 09:04 PM.
04-08-2007, 09:01 PM
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The old exhaust holes are covered with a hinged aluminum flap to relieve the air pressure like a vent. I got the idea from an Outerlimits boat that had them. They are primer grey now but will be painted to match the PPG Harelquin paint that changes from green to purple. I also need to paint the new hatches with the scoops from Skater. The other hatches were cut out for the massive Superchargers. The paint is $5,100 a gallon. Hopefully just a quart will do. 
Last edited by Brad Zastrow; 04-08-2007 at 09:08 PM.
04-09-2007, 05:05 PM
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04-10-2007, 11:09 AM
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Worlds Quietest Nortech...........
Here's the thread and the info on how they did it.
http://www.offshoreonly.com/forums/s...d.php?t=117884
Cougarman
Here's the thread and the info on how they did it.
http://www.offshoreonly.com/forums/s...d.php?t=117884
Cougarman
04-10-2007, 12:17 PM
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Brad, For verification, are the tails wet or dry ? Transom integrity ? One inch vent hose as on Nor-Tech tails ? Do you have any idea for the splash date ?
The total project looks super sanitary---nice work !!!
The total project looks super sanitary---nice work !!!
04-10-2007, 03:26 PM
#20
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Not worried about the transom. There are knee braces right next to the drives. No need for relief vents like the Nortech as I am not as deep in the water. The exhaust is wet at the tip of the tailpipe. That is a full 18" below the header exit not including the angle of the boat floating. This really is no different in concept than my MTI with the exhaust exiting underwater at idle. The MTI has nearly triple the horsepower with big cams and blower surge with zero reversion issues. If we ever get out of this 40 degree cold front I will splash the boat.
