VW variant flathead with water cooling !

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bmcj

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That's a tough one. Making it a flathead means that you change the entire volume and geometry of the combustion chamber. This means lower compression and a modified flame propogation path. You will likely suffer some major losses (if it will even run in the first place).

D-motor makes their own flathead engines, but I understand they we t through an extensive design and test program to get an engine that could breathe and combust properly. Slapping a flathead to an existing engine will require redesign of more than just the heads. You'll likely have to redesign the entire engine.
 

AIRCAB

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Why? What's your goal?
NO immediate goal, other than fact finding. I see D Motor has invested some resources into building a similar engine ! Using the existing VW cases, crankshaft, cams and other parts associated with that assembly, but with aluminum water cooled cylinder housings with valves and water cooled flat heads, may be a nice combination !

Steve
 

rbrochey

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Forgive me if I am a little confused when I happen upon threads like this... what would be wrong with just using the proven for over half a century VW existing design? I'm going to use the 1835 cc VW for my Cygnet... just wondering, being one who doesn't see the need to re-invent the wheel. ;)
 

BBerson

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A flathead can be very narrow in total width.
There was a highly modified VW article in EAA Experimenter. It had extreme short stroke and flat heads, I think.

I don't see the need for liquid cooling under 3600 rpm.
It doesn't take much fins to aircool. Just look at any Briggs and Stratton or Onan flathead.
 

AIRCAB

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Forgive me if I am a little confused when I happen upon threads like this... what would be wrong with just using the proven for over half a century VW existing design? I'm going to use the 1835 cc VW for my Cygnet... just wondering, being one who doesn't see the need to re-invent the wheel. ;)
Well if you have decided on that size VW engine, and it meets your needs, then what I am asking about is in relation to obtaining more horsepower, which you seem to not need.

Steve
 

Pops

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Forgive me if I am a little confused when I happen upon threads like this... what would be wrong with just using the proven for over half a century VW existing design? I'm going to use the 1835 cc VW for my Cygnet... just wondering, being one who doesn't see the need to re-invent the wheel. ;)

The most HP for the buck and the most reliable for the HP in a VW engine is the 1835 or 1914 cc.

Dan
 

AIRCAB

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A flathead can be very narrow in total width.
There was a highly modified VW article in EAA Experimenter. It had extreme short stroke and flat heads, I think.

I don't see the need for liquid cooling under 3600 rpm.
It doesn't take much fins to aircool. Just look at any Briggs and Stratton or Onan flathead.
I will have to look for that article !
 

Autodidact

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The camshaft on a type 1 is offset so that it would be a little wonky to line the lifters up with the valves on a flat head. On the type 1, each cam lobe actuates a valve on two opposing cylinders - kinda weird actually.
 

TFF

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Why not just get a Subaru if you want water cooled? Flat heads are compression limited because of the chamber shape, and flow is horrible getting fuel in and out. Those are the two things you take advantage of when going water cooled, because you can reject the extra heat.
 

Pops

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Several years ago Great Plains sold water cooled heads and a water pump for the VW engine. The cost was high and they were not on the market very long.
No, they were not VW water boxer engine heads.

Dan
 
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