One of these http://www.mshs.com/engine_sales/fpt_nef.htm a Arneson drive and Enjoy your boat!
Slippery when wet. "POD" Free Tunnel through Common Sense Engineering
I originally intended to put outboards on it and get the bigger and more useful cockpit, but with the swim step and the notch, the engines would be about 4 feet behind the transom! We would have had to extend the hull, and while that's not a HUGE problem, its another $10-15K.
I think the comments that a BBC and a SBC will burn pretty much the same fuel to generate the same HP is probably correct. And the weight difference is not that much. And the torque of a BBC is dramatically more.
There are some single engine versions of my boat, and they go nearly as fast as mine: a single 525 goes about 50 knots, mine goes about 55 knots.
I do lust for a diesel engine, but it still seems like the cost is so high (an additional $30K) that I will never see a savings.
Sounds like a BBC is the way to go.
For small blocks, check out the numbers on a 383 stroker (5.7L .030 over, 400 crank). Pretty impressive, reliable power.
I used to have a 35 Fountain with twin 500EFi's and now have a 27' Hallett with twin MerCruiser Scorpions which are 377" small blocks with Bravos. The speeds and Power settings are almost identical to what they were on the Fountain but the fuel burn is 50% of what the big blocks used. Just cruising and idleing in and out of the harbors my average fuel burn has been 12.5 to 14 gph and that includes some running at 4000 rpm and a lot of running at 3000-3200 rpm. They seem to be very efficient. Since your boat already is set up with twins it would be an easy swap, you would have the safety margin of a second engine to bring you in, I think that is important on the ocean. Your big blocks are certainly very saleable, so the conversion shouldn't cost too much.
All things considered, the single Diesel is your best choice, but also the most expensive. If you really love the boat and plan to keep it for ever, go DIESEL.
You might want to look into selling your boat and buy one that has the power that you like. That may be the most economical choice.
Fountain 35 Lightning Classic
West Hills, CA & Lake Havasu, AZ
By the time you buy new exhaust (you'll find none for SB's used) buy steel cranks and tough recip assemblies, good heads, and a good roller cam, all the marinizing pieces sea, pump etc. (good luck finding a single belt kit for a small block that will work) all the accessories are no cheaper than a big block
You need to walk a much finer line between idle quality and power output (head size and cam selection are more critiical for good manners) with a SB just because more cubes make for better manners all around.
After you are all done you'll have spent about what you'd spend on a big block.
My 406 in my little boat rocks balls, but it was no cheaper and a bunch harder to do than a bbc.
We can cut you a Smokin deal on a Red 625 with a warranty. Ask Uncle Dave how his single 7-10 is on fuel. PM me if you want
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