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Is there a benefit to installing a hydrofoil extension onto the anti-ventilation plate of a Yamaha 40-HP engine on a 1977 SPORT 13?

Tell me your experience with installing a hydrofoil extension onto the anti-ventilation plate of a Yamaha 40-HP engine on a 1977 SPORT 13.

BACK STORY: have a 1977 SPORT 14 and bought a used 1988 Yamaha 40-HP that had hydrofoil fins on the anti-ventilation plate. I removed the hydrofoil fins to do some work on the engine. I did not reinstall the hydrofoil fins on the engine when I mounted the engine on the boat. I have no complaints about the performance of the boat. The boat accelerates to planing speed nicely. The boat top speed is 34 to 36-MPH.

You don't need a foil appendage.

If you mount the engine to the transom in the one-hole-up position with the top bolt in the second hole down from the top, you should be fine.

Any tendency to for the bow to oscillate up and down can be addressed by shifting the fuel tank or battery forward a bit.

bobross wrote:Is there a benefit to installing a hydrofoil extension onto the anti-ventilation plate of a Yamaha 40-HP engine on a 1977 SPORT 13?

The benefit is mainly to the manufacturer and the retailer.