Adapting an engine to a trans

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Brian
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Adapting an engine to a trans

Post by Brian »

I'm building a stretched Monte Carlo (27') and it looks like I have access to an Aston Martin V-12 engine for it. It has more HP than the boat should have, but since it will live at a 6,200' lake, that will reduce the HP to a reasonable level.

There are obviously no adapter plates to mount a Hurth angle drive on this engine. One could be made, but I'm wondering why bother? If the engine and trans are mounted separately, with a short (maybe 12") drive shaft between them, wouldn't this work just as well? Clearly, the Hurth will have to be well-mounted to the motor stringers, and a cover plate fitted to the back of the engine, but other than that (and assuming I have the room), why not?

slug
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Re: Adapting an engine to a trans

Post by slug »

Just thinking out loud here;
First, there's the problem of cooling the exhaust ( water cooled?) Then if you solve that, you will have to make drive adapters from the back of the engine ( off the flywheel I assume, since the starter will probably engage here ) to a driveshaft with u-joints ( since the engine will move about on the mounts), then a u-joint on the transmission with a splined fitting to absorb any fore and aft movement.
I'd think it would be easier and cheaper to build an adapter for the trans to the bellhousing. Drive plates are readily available. (They absorb the shock loads )
Think it would be simpler to re-do a donor engine. There are lots available on the net.
Last month there were two complete 283 Chris Craft engines and transmissions for less than $1000 on Kijiji .
Doug

Brian
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Re: Adapting an engine to a trans

Post by Brian »

Thanks, Doug. I've looked at a LOT of engines, and if I don't do this crazy Aston Martin thing, I'll just install a 409HP ski boat package. A 283 won't come close to making this boat move along. We lose 20% at Lake Tahoe, and I think the Chris Craft 283's were nominally about 185 HP. I think I need about 380-400 to have plenty of power at 6,200' with a full load.

The thought of a spline to absorb movement is a good one. As far as finding a drive plate, there is not going to be one for an Aston Martin. The alternative would be to find one that was close to the size of the AM rear, then weld another plate on it and drill the holes to fit.

There are plenty of issues, that's for sure. I don't think exhaust is really that big of a deal though. For one thing, you don't have to have water-cooled exhaust. Wrapping the manifold and pipes with heat tape will keep the heat down, and the water can just go overboard. That said, one builder has used a Jag V-12 and managed to build a water jacket around the manifold.

The only reason for looking at the AM V-12 is that it would be totally cool to have in the boat. But not so cool if it doesn't work smoothly, so I'm not going to do it unless I can get really comfortable working through all the issues.

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jenko
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Re: Adapting an engine to a trans

Post by jenko »

The drive coupling is the easy one . Use the auto trans flex plate and bolt the Hurth drive plate to it with 1 inch spacers
the AM v12 was a Ford produced engine so it wouldn't surprise me if the bolt pattern for the ford Cleveland V8 bell-housing is the same bolt pattern .
In any case so long as the bell-housing clears the flywheel and doesn't interfere with the starter you can adapt to suit

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DesmoDog
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Re: Adapting an engine to a trans

Post by DesmoDog »

Brian wrote:I don't think exhaust is really that big of a deal though. For one thing, you don't have to have water-cooled exhaust. Wrapping the manifold and pipes with heat tape will keep the heat down, and the water can just go overboard. That said, one builder has used a Jag V-12 and managed to build a water jacket around the manifold.
Wrapping them with "heat tape" might keep the surface temp down, but it raises the temps of the manifolds and pipes themselves. We've seen temps exceeding 900C on exhaust components when they are shielded - that's very near the exhaust gas temp and above what some materials can handle for extended time. At the very least your pipes will need to be made out of a 411 series stainless, or whatever the step above the typical 409 series is. You might also look into ceramic coating if this is the route you're going down.

Maybe you could ceramic coat and/or shield the manifolds, then inject water into the pipes downstream of the manifold? The heat has to go somewhere. Shielding and wraps just move it on further down the line, adding wear will help get rid of it.

IMHO if it was easy to do with shields and wraps, you'd see more of that and fewer complex castings/systems for water cooled manifolds. I'm not saying it can't be done, I'm saying I wouldn't count on it being a simple process of buying some header wrap from Summit and calling it good.

All that said, an Aston Martin powered Monte Carlo would be sweet...
-Craig

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aero_dan
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Re: Adapting an engine to a trans

Post by aero_dan »

Hey Brian, For what it is worth, I just mated a late model John Deere/ Yanmar in my Takiuchi track hoe. Everybody in the universe told me it could not be done. I found out the original engine was a Yanmar derivative, so I went to Motion Tech in Boise to help with the couplings. A month or so later, and she purs with the coolest factory-looking setup. All I am sayin is, If there is a will, there is surely a way. I understand about the "engine in the water" thing, but I would not let that bother you. If I remember right, there are a couple machine shops around Kalifornia that will build you the "missing links". Forget the mindset of "well it was made for X model of car", and look at the SAE pattern used. Like it is sorts stated above, there is a lot of off-the-shelf stuff that will fit, if you do not get hung up in the autoparts places. Isn't this why we build instead of buying your typical Tracker or Glastron???... And BTW, I think that would be one cookin and coveted hot machine to have. I say press on and PLEEEAAASE keep us all informed here. Cheers!
Better, faster, cheaper. Only ever found 2 of the 3! (But still lookin.)
So many boats, ...so little time.

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jenko
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Re: Adapting an engine to a trans

Post by jenko »

That said, one builder has used a Jag V-12 and managed to build a water jacket around the manifold.
I have not yet built the manifold but I am about to start the outer casing will have to be put on in two parts but here is a couple of pics of what I intend to do.
I want to make it out of rolled 316 in a cone shape but it is proving hard to get it rolled in the dimensions I want, so I might end up using straight pipe ,I can afford to lose a bit of HP as there is plenty to spare ,
Attachments
bex12-2.jpg
bex.jpg

Joris
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Re: Adapting an engine to a trans

Post by Joris »

jenko wrote:
That said, one builder has used a Jag V-12 and managed to build a water jacket around the manifold.
I have not yet built the manifold but I am about to start the outer casing will have to be put on in two parts but here is a couple of pics of what I intend to do.
I want to make it out of rolled 316 in a cone shape but it is proving hard to get it rolled in the dimensions I want, so I might end up using straight pipe ,I can afford to lose a bit of HP as there is plenty to spare ,
Making a cone isn't really easy unless you have the equipment for such a special job. It's a lot easier to cut a V-shaped strip out of a tube and pull the edges together then tig-weld them. Welding a waterjacket around a OEM-manifold might work but isn't without risks if the manifold is cast iron.
Joris

Brian
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Re: Adapting an engine to a trans

Post by Brian »

Wow, thanks for the encouragement you guys! Clearly, the spirit of innovation is alive and well here.

Gayle thinks I'm crazy, and there's no question about that. But the image of opening the hatch and looking at "Aston Martin" on the engine cover has me by the you-know-whats! I'm scared of what it might entail to make this monster actually run, with all the advanced functions electronically tied to it. But I'm game to try. The power is probably way too much, as even a 27' version of the Monte Carlo shouldn't be going more than about 55 mph. I'm thinking of some sort of rev limiter!

Jenko, thanks for the drawings. I'm a long way from dealing with the exhaust, but I'm hoping there are various possibilities that aren't too complicated. Did you consider making a split box, with one half that fits between the engine ports and the manifold, and the other half on the outside? Probably not as pretty as what you are doing, but maybe easy. Also, what about using an existing water jacket manifold from a six and making an adapter plate? Finally, not considering cost, aren't there places that can build water jacket manifolds?

Also, I'm not sure I follow you (jenko) on the drive coupling, but it sounds encouraging. When I get the engine, I'll post some photos of the rear. This AM V-12 wasn't made by Ford, but is from a Vanquish S. So about 520 HP at sea level. I doubt the bolt pattern is anything like anything (if you know AM's, you know what I mean!).

And I take the point on wrapping the exhausts. If that worked, why would there be an industry making water jackets?

Check this post later for an update on the Aston Martin Monte Carlo….I'm going to need LOTS of help!!

fergal butler
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Re: Adapting an engine to a trans

Post by fergal butler »

Some of the early offshore "Tremletts" powerboats over this side of the pond were powered by one or two V12 Aston Martins

Image

Brian
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Re: Adapting an engine to a trans

Post by Brian »

Not to get too far off into Aston Martin Land, but the DB5 engine was a 6, not a 12, and even though they advertised the Vantage option at 325 HP, it was nowhere near that (I have one). More like 290. A pair of them would be interesting, but if you can find one they are probably about $100,000 apiece! Interesting 1965 ad though!

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jenko
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Re: Adapting an engine to a trans

Post by jenko »

The 1965 AM 6cyl is actually a jaguar 6 cyl engine with their special wider valve angle head developed for racing

Brian
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Re: Adapting an engine to a trans

Post by Brian »

Jenko, none of the DB engines were Jag based. The were ground-up engines, designed by Tadek Marek for AM. They look similar, with the twin overhead cams, but they are entirely different.

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jenko
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Re: Adapting an engine to a trans

Post by jenko »

I sit corrected :lol:

Brian
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Re: Adapting an engine to a trans

Post by Brian »

Just found out the Vanquish V-12 I thought I was going to get is not going to be available after all. But I'm going to keep looking. Got to be some wrecks out there somewhere!

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