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d1mbu1b
10-20-2005, 07:59 AM
Has anyone converted a GIL offshore wet system to a dry exhaust?
Can you plug the ends and route the water through the hull?

I am looking into this, so, not to limit my cam selection.
Has anyone considered something like this?
Where would you route the water?
It might be nice for the driver to see it, this way you
know your sea water pump is working.

Any thoughts?

mrfixxall
10-20-2005, 09:14 AM
i dont know ware your from but here in ill its not legal to run dry exhaust because its a fire hazzard.coast guarg says that your exhaust must bblend with water..if youe looking for that crisp header sound then i suggest you buy a set of stelling headers that are water cooled and the water dumps out at the at the end of the header extension....

mrfixxall
10-20-2005, 09:23 AM
p.s. if yor concern is about water pressure,most sea pumps hace a 1/8" plug in it for a water pressure guage,,just sonthing to look into..............

Rootsy
10-20-2005, 10:45 AM
I've seen plenty of GIL and other setups that leave a fine mist of water in the exhaust to help cool it a bit.. and the majority is pumped out the transom through a hose and fitting...

as far as converting i am not sure of exactly what you'll have to do but at a minimum i would guess replace the elbows to ones that are dry or semi-dry...

just exactly how much camshaft do you plan to run????

if you have GIL's and want to do this i would suggest giving them a call and asking them... they'll know better than anyone...

d1mbu1b
10-20-2005, 12:04 PM
thanks for the replies.

The water pressure gauge is a good idea.

I wish to keep the exhaust water jacketed, just not mix the gases and water at the end of the pipe.

I'll call GIL as suggested.


I plan on running a pretty aggressive cam with rhoads Vmax lifters.
I am just worried about water reversion.

GEOO
10-20-2005, 02:05 PM
I ran into water reversion with a big cam. My Stainless Marine custom pipes dumped water into the exhaust at the transom and mixed the last 4" going out the pipe. I had the inside of the pipes welded and added a water output to the top of the pipes and plumbed the water out the transom. My pipes hit the water at idle so I also added Shot-Gun Marine Flaps which advertise they also stop reversion pulses.
Big cams and slow idles equal reversion.
Test it...You can run your boat at idle, turn it off, remove the exhaust elbow and look in the manifold if you see water in the bottom of the manifold ....you got water...
Good Luck..

See elbows off rear of exhaust:
http://www.donzi.net/forums/attachment.php?attachmentid=2298



See flaps and two water dumps for exhaust, third for intercooler.
http://www.donzi.net/forums/attachment.php?attachmentid=7145

d1mbu1b
10-23-2005, 06:47 AM
GEOO,

Thanks for the tips. That is exacly what I was asking about.
I would have never thought about putting the water outlet on the top.
That makes a lot more sense while running. Do you recommend
a fitting on the bottom to drain the rest of the water out while storing?