First off, I know that one of the problems and solutions of these boats is the capacity to carry enough fuel. Otherwise a gas turbine or a blown big block Chevy would make way more power if it wasn’t so thirsty.
yes, no & depending. If it is a slick-water a/o speed game, sure: gas HP rules. If it is in seas, there is only so much power can be applied/used, but yeah, amount of fuel is a limiting factor, too.
I think you need a light weight efficient motor that will allow more fuel capacity on the boat. ... Any heavy diesel engine would negate the advantages gained by the fuel savings. I know what I would do. The Cummins is just too heavy.
not necessarily. "Sufficient" Mass is absolute necessity in an endurance boat, both for structure and inertia. I CAN get a 43' boat built that is as light as two sofa pillows and a popcorn fart, but that would be like burying gold bars in a swamp.
As you indicate further down, mass (when planned and placed) is valuable and necessary.
Torque matters in marine. A fully wet boat and with a half-load run abt the same fast. You burn more fuel heavy, of course, but then you creep back up to 2miles/gallon with the same settings, and maybe 1-2mph more.
That is a real difference between gas and diesel in endurance. The gas engines are more subject to breakage at heavy + redline. That is an open secret Buzzi has used for years: get out in front and make them stress the equipment.
Electronic engine management would be critical, to fuel savings.
I'm not so sure. In fact, HPCR actually carries a ±10% overage. Bosch says 'up to 10%' but b/c of all the other changes necessary to run HPCR, it is not apples-to-apples comparison. I-F, SeaTek and FPT say it is at least 10%. HPCR cuts down on smoke and noise. It is not more efficient.
I would also use synthetic diesel in that it carries more BTU’s of heat energy per lbs.
You're peeking over my shoulder, aren't you? Shell and BP (among others, I'm sure) make a +140k BTU kerosene, and Shell, anyhow, is willing to discuss additional Cetane and lubricity.
... I would use a Duramax based power plant. It would not be a big engine and weight would be the part of the design.
Regardless of Gale Banks blathering abt how the DM is all things to all people, near and far, wet or dry (or should be, anyhow), the ONLY successful marinized DM comes from Finland, and is rated VERY conservatively, less that 400, IIRC.
Hot DM for Inshore? As a diesel variant of a Merc 725, maybe, but why? Out of sight of land, no way. Not until somebody else has run them 10,000 hrs under load.
I would use a aluminum bock, but it would not be a LSM block, ...
Forget the aluminum LSM for a second. I can make a 12V, P7100 'B' at +800hp for ±1000lbs. Innovation sells all the 5.9 600hp they can make, and those are substantially de-tuned. True, the only Cummins part# in them is the crank, but the CGI block is Cummins spec to the gnat's whisker, same weight.
I don't know what a fully maranized DM weighs, but it can't be too far south of half-ton, can it?
I know their (Innovation's) kinks (well, mostly, anyhow, there is some mil-secret tuning but it's trivial), and that is pretty much what I am doing. It's conservative, really.
LSM Aluminum Blocks cost $12k, btw. Dan Scheid (who has built more LSM blocks than anybody) says that as far as he is concerned, with my conservative build, a 2000hr life on Al is not an issue ... but he does not think they would be rebuildable for another 2k, where a castiron Cummins would be.
I don't think they would be up to the task. your talking half a million for a pair and a spair motor program . lots of dyno time.
Yeah, offshore racing is not for the faint of heart, not thin of wallet. You have to have at least one spare motor, plus plenty of parts. Scheid thought a ± number for an Aluminum build would run about $70@, and that not only includes the internals: Hamilton + C-Tech, P7100, Mahle Steel tops, but also includes some metal work, moving the starter and getting rid of the belt for the generator, water-pump and PTO.
My bare hull will be in the 6.000# range: extra-heavy bottom and top made of spider-silk and ghost turds. Fitted dry, with a pair of cast iron Cummins 5.9 blocks, controls, electronics, capsule, fluids, safety gear, etc., double that.
1,000 gal of fuel is another 3½ tons, but the first ton of that will go pretty fast, and the only runs I think of that will come close to needing over 500gal are Venice-Montecarlo, NYC-Bermuda-NYC (with a fuel stop, of course), and KW-Cancun-KW.
FWIW, the diesel engine that I think will end up being incredibly special for all kinds of stuff is that 'New' Light RAM diesel, the VM Motari 3.0L. At 300hp, it is WAAAAY de-tuned, weighs less than 500# and is tiny enough to fit in the back of your Wranglers, with enough space left for a can of Skoal.
wned:?
