20 Super Stock Hydroplane Power

The 20 SSH class uses the the Yamato model 80.  This is a stock racing engine developed specifically for use in Japan’s multi-billion dollar pari-mutuel boat racing industry. These motors were built to run heat after heat, day after day with perfect reliability at racing speeds. Therefore, they have been "over-designed" in relation to the job they perform. The motors were manufactured from 1974 until 1979 at a rate of 1,500 motors per year. Approximately 1,100 motors were imported into the United States.

The Yamato 80 is a water-cooled, two cylinder gasoline engine, with 327.8 cc (20 cu in), and 30-hp at 7,000 rpm.  Features include a loop scavenging combustion system, pyramid reed valves, one piece connecting rod, precision ground full circle pressed together crank, ball and roller bearings throughout, high capacity magneto, integrated fuel tank, and an internally tuned megaphone muffler. The cooling system is supplied by the propeller forcing water into two intake orifices located aft of the propeller. The prop shaft rotation is counter clockwise. All exposed parts are made of corrosion resistance material. All fasteners are made of stainless steel with the exception of parts, which require additional strength.