Abstract: An outboard motor boat having an aft configuration with a new and improved transom configuration that includes a stand alone, upwardly projecting, cantilever shaped central transom portion. The transom configuration also includes a transom mid portion connected to the base of the central transom portion and a lower transom portion connected to the transom mid portion. The central transom portion is positioned centrally between a port side through transom walkway and a starboard side through transom walkway. The port side through transom walkway and the starboard side through transom walkway project aft from the aft deck along either side of the central transom portion to a position at least adjacent a portion of the side of an outboard motor position at the stern of the outboard motor boat.

Abstract: A marine exhaust system for boats powered by an internal combustion engine is disclosed. An exhaust chamber is located in the stern of the boat and is connected to the engine exhaust manifold. A submerged exhaust port emits exhaust gases below the water level to silence exhaust noise. The exhaust port has a recessed opening so that relative movement of water past the port assists in drawing the exhaust gases from the chamber. Atmospheric vent holes communicate the chamber with atmosphere to exhaust gases when the boat is idling or operating at slow speeds.