Forgot to mention this is an I/O application.

makes sense, the cam is going to cause the motor to lope

So it sounds like through transom exhaust with a dam prevent water from getting back inside. I am a bit confused though, because it is an I/O it has to be water cooled, the water is sucked up to cool the motor and dumped into the exhaust to drain…..or so I thought??

you’ll need completely dry. Water cooled of course. And headsets.

so how is the water cycled then? I assumed it was dumped in the exhaust?? If this was a sports car I’d know where to go, haven’t been into boating for very long…and the boating season where I live lasts for about 3.5 months is all.

Dry manifolds and pipes still can have water jackets. The cooling water will just dump outside of the exhaust, not into it. Expensive but sounds sick.

Typical "wet" marine exhaust has the cooling jacket water being dumped in with the exhaust gas at some point before the exhaust leaves the boat.

With dry marine exhaust, the water doesn't go from the cooling jacket of the exhaust, into the exhaust gas stream and out the tailpipe.

The water is dumped overboard via a separate hose that is usually plumbed from the cooling jacket, to a through hull fitting.

Dry exhaust is still water jacketed as wet exhaust. Don't let the term dry confuse you. The difference being no water enters the exhaust stream as wet exhaust does.
There's many variation also as to where water can get introduced if it does so to speak in a dry exhaust.

Thanks everybody I appreciate the knowledge.

Our dry exhaust…