anyone ever try putting a 2 speed transmission into a boat?

[dana]

sounds ridiculous but i always wondered what it would be like to cram a two speed transmission from a revo or something into a boat

[Fluid]

Folks have talked about it for years, but I have never read of it actually being done. The only advantage to it I can see is for SAW racing when it might allow slightly faster acceleration when using a huge prop. For oval racing it is just one more thing to go wrong. KISS.



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[driftah]

not to mention the toque kick when it shifts into 2nd gear youch the rpms may smoke a tranny lol

[keithbradley]

I have worked with a guy who built a 2 speed lower unit with a torque converter for real boats. Mercury marine bought it off of him and the rights to it, but never really did much with it. As far as I know they bought it just so they wouldnt have to compete with it. I think 2 speed units have been used in race boats though...
Having a two speed in something powered by a gas engine would reap a larger benifit than in electric model boats IMO. With gasoline engines, particularly N/A race engines, there can be a drastic difference in torque and power when comparing an RPM range inside or outside of the engine's power band. Brushless electric motors may operate a little more efficiently at a particular RPM, but aside from cogging at very low RPM, they pretty much make torque everywhere. So there is less need to keep the engine at a consistant RPM range, which would be the purpose of a multi-speed transmission.