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The following is an update on the Bass-Tohatsu performance. We have entered one NBRA and one APBA race. Before the year is over, we want to attend an AOF race and probably another local APBA race. E-mail me with your questions or if you would like other information.
Power head: The center crank pins are spot welded in two places per Tohatsu America recommendations. A throttle connection and a plug for the kill switch are installed. Larger Tohatsu carburetor jets are installed and the timing is set at 25 degrees advanced at full throttle. The power head is otherwise completely stock.
Tower Housing and Lower Unit: An adapter for the Bass Machines tower housing allows the use of the Tohatsu stock saddle and clamp system. Water supply is routed within the tower housing to the stock connection at the power head. Water is pumped to the power head through the Bass Machines standard pump system. The lower unit is a standard Bass Machines with Bass Machines 17:17 gears.
A&H 250cc hydro: The boat has a 35-inch wide bottom, 77-inches after plane, and approximately 2-inches lift. This boat has previously performed well as a 250cc at 85 MPH, and served as a test bed for D-mod R&D work. This hull was chosen because it is available (Sid owns it) and is a safe ride for different drivers. The boat and engine weighs approximately 325 pounds.
Setup: The propeller shaft is set at the bottom of the boat per DSH rules. A slight tuck was tried, but level worked best with the boat as the hull runs close to neutral balance. This setup allowed the boat to float off the water without becoming too loose for a new driver. Overall handling was rated very good by the drivers.
Propeller: Various types and sizes of propellers were tried and found that generally the D-stock propellers did not work well. The best propeller is a 7-3/8 diameter three blade, round blade shape with a medium cup at the trailing edge. The mid section of the blade has a pitch of 11/11.5/13 inches and at the tip of the blade has a pitch of 9/9/11 inches.
Speed & RPM: The engine ran at 6,600 to 6,900 RPM, about 73 to 75 MPH, depending on the weight of the driver. Acceleration is very good.
Performance under Competition:
Cullaby Lake Regatta (APBA), DSH - June 26, driver Rick Keller finished D-stock in second and third place. Rick started with the pack both heats, lanes two and three. He drove it hard. June 27, Driver Jon Steen finished D-stock in second place both heats. Jon started with the pack in lanes two and three and pushed it real hard, only as Jon can do. There was good competition in D-stock both days. There was a three boat race out front and Jon Steen drove the boat hard competing well with the other two boats. He would have placed third in the last heat except that the second place boat missed a buoy in the last turn. Jon and the boat weighed approximately 500 pounds.
Cullaby Lake Regatta (APBA), DMH - June 27, driver Rick Keller finished second place both heats in D-mod. There was only one true D-mod that started out front both heats but did not finish. The wining boat both heats was a 44xs D-stock.
Banks Lake (NBRA), June 19 and 20, driver Sid Bass placed second three heats and first one heat in a combination of mod, stock and pro boats. Close competition was provided by one competitive D-stock.
Power head: The center crank pins are spot welded in two places per Tohatsu America recommendations. A throttle connection and a plug for the kill switch are installed. Larger Tohatsu carburetor jets are installed and the timing is set at 25 degrees advanced at full throttle. The power head is otherwise completely stock.
Tower Housing and Lower Unit: An adapter for the Bass Machines tower housing allows the use of the Tohatsu stock saddle and clamp system. Water supply is routed within the tower housing to the stock connection at the power head. Water is pumped to the power head through the Bass Machines standard pump system. The lower unit is a standard Bass Machines with Bass Machines 17:17 gears.
A&H 250cc hydro: The boat has a 35-inch wide bottom, 77-inches after plane, and approximately 2-inches lift. This boat has previously performed well as a 250cc at 85 MPH, and served as a test bed for D-mod R&D work. This hull was chosen because it is available (Sid owns it) and is a safe ride for different drivers. The boat and engine weighs approximately 325 pounds.
Setup: The propeller shaft is set at the bottom of the boat per DSH rules. A slight tuck was tried, but level worked best with the boat as the hull runs close to neutral balance. This setup allowed the boat to float off the water without becoming too loose for a new driver. Overall handling was rated very good by the drivers.
Propeller: Various types and sizes of propellers were tried and found that generally the D-stock propellers did not work well. The best propeller is a 7-3/8 diameter three blade, round blade shape with a medium cup at the trailing edge. The mid section of the blade has a pitch of 11/11.5/13 inches and at the tip of the blade has a pitch of 9/9/11 inches.
Speed & RPM: The engine ran at 6,600 to 6,900 RPM, about 73 to 75 MPH, depending on the weight of the driver. Acceleration is very good.
Performance under Competition:
Cullaby Lake Regatta (APBA), DSH - June 26, driver Rick Keller finished D-stock in second and third place. Rick started with the pack both heats, lanes two and three. He drove it hard. June 27, Driver Jon Steen finished D-stock in second place both heats. Jon started with the pack in lanes two and three and pushed it real hard, only as Jon can do. There was good competition in D-stock both days. There was a three boat race out front and Jon Steen drove the boat hard competing well with the other two boats. He would have placed third in the last heat except that the second place boat missed a buoy in the last turn. Jon and the boat weighed approximately 500 pounds.
Cullaby Lake Regatta (APBA), DMH - June 27, driver Rick Keller finished second place both heats in D-mod. There was only one true D-mod that started out front both heats but did not finish. The wining boat both heats was a 44xs D-stock.
Banks Lake (NBRA), June 19 and 20, driver Sid Bass placed second three heats and first one heat in a combination of mod, stock and pro boats. Close competition was provided by one competitive D-stock.