underwater muffler

[Savage04]

i have a custom built nitro v hull and i wanted to know if i could make it so the muffler comes out under the boat.. i know i can do it but will it work or will the motor just die as soon as it hits the water?????




THANKS

[Doubledog]

Think about this: The boat is planing out (riding on top of the water) ? If so, then if you've got the exhaust coming out at the back-lower portion of the hull, then its still going to be exposed till you slow it down and the water line comes back over it.

Back to your question: I think the back pressure would cause a problem when at slower speeds. If the boat was idling around it 'really' would, but its not going to do that. LOL.

What other ideas are out there.?

[Hydro Junkie]

I built the Dumas 30" Pay N' Pak as my first boat. Not wanting to have the exhaust visible, I ran it out the bottom of the hull. Due to the backpressure, I couldn't get the little HB 20 to rev up or get the boat on plane :mad: While an underwater exhaust would look cool, it WILL AND DOES act like an exhaust throttle, limiting engine rpms. It wouldn't be AS BAD coming out the transom of a deep vee, but as DD has pointed out, it will cause SIGNIFICANT PERFORMANCE PROBLEMS. When you slow down, the water coming up behind the boat WILL cause an INCREASE in backpressure, probably killing the motor. I would recommend saving this idea for a gas powered boat, where the effect wouldn't be as run stopping :(