And the planning begins!

[cracked_ribs]

I wouldn't use a Carver or a Silverton to CROSS an ocean or anything, but coastal cruising, there's no reason they couldn't handle it unless you are just hell-bent on rough water performance, say.

They're not really optimized for trawler speeds, though, and I think you would struggle to get one to ten knots with that power. You could easily run a pure displacement boat with even a single electric at the specs you're describing though. Some of the BC troller boats that were built with 3-53s were totally overpowered when not full of 8 tons of fish, and they probably had roughly similar numbers in continuous output marine versions, I'd guess. They're slippery boats with canoe sterns and the bigger ones are pretty damn seaworthy. The little ones, say 28-32', worked the whole BC coast up to Alaska. I'm not saying you should look for one of those, specifically, but just if you want to maximize space and use unconventional and possibly reduced power, that's a hull form that I'd look at, personally.

[TomW1]

Another point I would not use a Mitsubishi electric engine for ocean use. Ocean corrosiveness would cause to much damage in a short time. Stick with marine diesel engines or electrics built for marine environments. Both for better mileage and safety.

[Fuzz]

I think many people do not understand the difference in moving a boat through the water and moving an auto over the land. With an auto you use maybe 40-70% of the motors power for a very short time to get up to speed or climb that hill. the rest of the time the motor is just loafing along. With a boat you are pulling a higher percent of power out of the motor for an extended time. You will never pull 80% power for hours on end from an auto but you could do it with a boat no problem.
Either a sailboat or a slippery power hull will be the cheapest way to cover lots of miles under power. I have a good friend with a Skookum 53 sailboat hull. The boat is set up to commercial fish and he runs it a lot. The boat is powered with one 3-71DD. An average year is 6000 hours on the main. Yes I said 6000! The little Detroit gets rebuilt every 5 years/30,000 hours. It is now running on its 3rd rebuild with close to 110,000 hours on the clock. He runs the boat from the Russian border up by Nome to the south end of SE Alaska.

[TomW1]

Very good point Fuzz. A boat diesel is going to be running at a higher throttle speed for longer times than an auto. My auto runs at 1900-2100 most of the time. When I was on diesel boats they were running in the 3500 rpm range most of the time for long periods of time. I believe this is what you are getting at.

[Fuzz]

An auto engine rated at 300hp will be making 30-50hp 95% of the time. A boat engine rated at 300ho might be making 240hp 90% of the time. you try to do that to a gas engine and you will gut it in short order.

[cracked_ribs]

Yeah, duty cycle on a marine engine is pretty harsh. Some stuff you can get away with it...a GM 350 truck motor holds up fine in a boat, but it's already under-stressed in its auto application.

I don't really know anything about electric car components and duty cycles and load ratings. Are they rated for continuous output? That's the real question there. Marine engines need a continuous output rating to withstand the non-stop load of driving a boat through the water.

[cape_fisherman]

I would choose the boat design now...yes, build one! Don't worry "too" much about power options. Build the boat knowing what adequate power will be. I guarantee that in 11 years the options will be very different than what are available today. It doesn't make sense worrying about what will, or will not, work today. Tomorrow is coming. Spend your time building the boat, and worry about powering it closer to the time it needs to be powered.

[TomTom]

Have you looked at any of the used boats that come up for sale on Richard Woods website?