Why marinize the exhaust manifold?

[Terra Nova]

I really like the dual starters.

[Cheechako]

Dry exhausts have been used a lot in commercial boats, done right they are great. But they are expensive also. For most rec boats I would prefer to not re invent the wheel and stick with the wet exhaust. But once installed... I would imagine dry exhaust is less trouble prone and less risky than wet.... for the reasons mentioned previously in this thread.
We built some military craft with dry exhaust and which had a requirement to run out of the water for 15 mins minimum.... it turned out they would run that way a lot longer...

[captlloyd]

Originally Posted by SkiprJohn

Just curious but where did the exhaust exit the engineroom?

Actually being a steel hull, I just ran the exhaust along the bottom of the hull (1/4'') and out through the starboard bottom corner of the transom. Part of the beauty of steel hulls. I thought there would be more heat to contend with as the engine is a turbo. Not so. I did have a pretty big enclosure though. I had a Kabota engine on a O-turn mower and I saw very little heat being generated by this engine. As far as having the steel exhaust pipe exiting the fiberglass hull, I would fabricate a stainless plate which would be adaptable to the steel exhaust pipe, (coupling)