View Single Post
Old 03-24-2008, 03:31 AM   #117
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 22,553
RE: Electric Boat Engines

This means that for every 100 HP out of the engine you could obtain as much as 95 hp at the propeller shaft or as little as 61 HP. At the high end this compares favorably with the 3% to 5% loss typical of a mechanical transmission (although not all electric motors can be directly connected to the propeller shaft).

All this is fine , but if you look at the prop load curve , and shift it closer to the power aviliable curve you end up with a CRUISING PROP.

The power match is in the much more efficient area , although the mfg will be unhappy at the loss of top rpm, so the possibility of an overload from throttle position.

EGT gage for $150 solves everything , iIF the operator understands what he is seeing.

AS more and more engines in boats become electronic injection , this objection dissapears (brain dead operator OK) , as the computer wont allow an overload.

Of course the unfixibility of the on board electric stuff means only cruising with in the std reach of Sea Tow.

FF
FF is offline   Reply With Quote