Awhile back, I asked if anyone knew about techniques to temporarily
increase the power of a diesel similar to using nitrous oxide in a gas
engine. Today I got a JC Whitney catalogue and in it was a kit for
doing just that. I guess you would have improved power until the
nitrous ran out or till your engine overheated.
I wonder if you could adapt it for a small sailboat diesel.

Now, i wonder if you could have a duel fuel/duel ignition system where
it ran on gasoline for acceleration and on diesel for constant speed.