1966 John Allmand Hardtop 6.5 Optimizer Diesel repower and upgrades

res0wc18

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Well after a long read-up on here and various other places. I have nearly decided to purchase a center mount turbo long block from Teds trucks and convert it over to marine to replace the tired and now broken 340 horse 454 in my 66 John Almand 23' offshore hardtop.

From what I can see and read these new optimizers are a very good engine now that they have gotten the bugs worked out.

Here is what I am debating.

Running it in N.A. form with a matching CUCV type injection pump which would put it around 170hp and 290 ft lbs? This would give me all the block/bearing upgrades WITH the piston oil cooler jets. You can never have enough cooling on a marine engine. For longevity and high sustained RPMs this is where its at.

Or

Converting it over to a procharger blown engine. Yes there is aftermarket marine turbo systems for this thing and they are super spendy and create a **** ton of heat and complicates the exhaust routing and on and on.
This would include lowering the compression via the use of those Cometic gaskets to around 18:1 or so so again I don't have to worry about long term RPMs.

Prochargers are awesome units. Good response good boost and little heat. I have even roughed out some ideas for a water to air intercooler to cool the charge as much as possible. I would need a separate heat exchanger though as running raw salt water through aluminum intercooler is bad news.

I live in the puget sound and with the wide open boating space we have the engines need to be setup for 80% throttle at a 100% duty cycle.
Add to this all of my diesels run off of WVO(waste vegetable oil)
and it would be awesome to have a boat to run around 25mph or better and not have to worry about over heating or fuel economy.

The boat weighs 4300 pnds worst case setup as I have described

Here's some pictures for ideas. She's a big boat. I basically was going for the smallest boat I could get with a real marine tranny yet while having a hardtop and being able to fit in my 40x30x16 shop on the trailer and truck. This setup clears with enough room to move around and work still with it secure and the truck parked.

Osco makes nice marine fresh water cooled exhaust manifolds so that's a non issue. Everything else from the Big block will bolt right on with minimal effort and what doesn't I can cut weld blast and paint so it does

i want to raise the hardtop about 24" or so so i have even more stand up room with new Diamond Sea Glaze windows and repaint/re gel the entire boat so it looks good/clean/new.... Its amazing how built this darn thing is. all fiberglass no wood in anything of water contact etc. in fact the only wood i found was part of the anchor locker lid. the rest of the boat seems to be fiberglass/foam core. its pretty impressive.
 

res0wc18

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Re: 1966 John Allmand Hardtop 6.5 Optimizer Diesel repower and upgrades

IMG_20140227_205101_875.jpgScreenshot_2014-04-19-10-20-21.jpgIMG_20140227_205035_010.jpgIMG_20140227_205001_027.jpg

i want to raise the hardtop up to a design similar to the one in the picture
 
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res0wc18

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Re: 1966 John Allmand Hardtop 6.5 Optimizer Diesel repower and upgrades

yes he was actually one of the reasons why ive been lurking so long.

his boat is 3 times the weight of mine. that i do know.

ive been talking to some of the performance shops that specialize in the 6.2/6.5's and with a free flowing exhaust such as the marine manifolds are and a performance camshaft i would be right about 200hp and 330 ft lbs of torque respectable power and way way more fuel mileage running of veggie oil!
 

Willyclay

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Re: 1966 John Allmand Hardtop 6.5 Optimizer Diesel repower and upgrades

I had my eye on a Bertram 20 with the same goals in mind but it got away from me. Your weight difference is huge and the plan sure sounds good. I will enjoy the ride!
 

res0wc18

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Re: 1966 John Allmand Hardtop 6.5 Optimizer Diesel repower and upgrades

nice! the biggest issue im working with is the trailer. i need to switch to a decent bunk trailer setup so i can get it as low to the ground as possible so i can raise the hardtop by 24" so i have more usable headroom etc etc. since this boat has a real inboard tranny and prop setup the trailer is kind of a nightmare to get it as low to the ground as possible to allow me to raise it 24" while still being able to get it in my 10 foot high shop door with it still on the trailer.
 

Willyclay

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Re: 1966 John Allmand Hardtop 6.5 Optimizer Diesel repower and upgrades

That's a pretty significant challenge just to get started. You could start a separate thread in the Trailer Forum dealing with that issue only and see what comments you gather. Good luck!
 

res0wc18

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Re: 1966 John Allmand Hardtop 6.5 Optimizer Diesel repower and upgrades

yes i think i have it figured out though. My old school trailer has that double frame crap they did back in the 70s where its two tub frames one with the axles bolted to it and the other is the main frame runner that attaches to the trailer tongue. ive found a nice used galvanized rolller im going to convert to bunk so i can get the boat as low as possible to the ground.
 
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