My next project: the Porsche 917 from 1970, detailed as much as possible.
Starting with the engine.
12 cyl. 180° V-Engine.
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That’s called boxer engine, it’s not V anymore if it’s 180°.
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Do not start a discussion with wrong infos!
Interview with Hans Mezger - the designer of the 912-Engine - this is the internal porsche code to keep the development secret in 1969:
The 917 engine is not a boxer engine!
‘The first thing we did was to put two design drawings of the 911 six-cylinder engine one behind the other and see if it fitted,’ says Mezger. Nevertheless, the popular claim that the 917 engine is nothing more than two coupled 911 engines or even an eight-cylinder engine from the 908 extended by four cylinders is simply nonsense: unlike the previous engines, the twelve-cylinder engine, known internally as the 912, is a V-engine with a cylinder angle of 180 degrees. On the one hand, this saves length because the offset between the left and right cylinder rows now corresponds to just one connecting rod bearing width and not half the cylinder spacing.
Above all, however, a V12 requires only six connecting rods and eight main bearing journals instead of 12 or 14 compared to a boxer engine - in addition, the diameter of the connecting rod journals can be slightly reduced for the same load. As the required oil pressure can now also be lower, this, together with the smaller bearings, significantly reduces friction losses.
911 and 908-Engine are boxer, the 912 is a V-Engine with 180° bank angle!
I know what i say - tons of books from the right persons involved in the development of Porsche are more prove as useles statement written on webpages on the internet.
BTW: the Ferrari V12 (used in F1 in the seventies) have also 180° bank angle - they are not called Boxer.
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That is a great start! I look forward to future updates. 
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If it’s not boxer is a flat 12, the V nomenclature is given by the shape, if it’s 180 degrees it’s not a V it’s a ——
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Great, another person who knows ‘better’ than the engineer who designed the engine.
The engine is simply a V opened up to 180° - like the Ferrari V12, which was used in the 312T, 312T2, 312T3, 312T4 and 312T5, for example. In a V-engine, whether 60, 70, 80, 90 or 180° bank angle, a pair of pistons always share a common bearing journal on the crankshaft. In a boxer engine, each cylinder has its own bearing journal and the crankshaft requires more bearings. In a V-engine, the movement of two opposing pistons is always in the same direction. In a boxer engine, the opposing pistons always move in opposite directions.
Curiously, Porsche’s 6- and 8-cylinder boxer engines are also referred to as Flat-6 and Flat-8.
Flat-X only says: 180° and the number of cylinders - but not how the cylinders are attached to the crankshaft!
Actually the same person doubling down. 
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Some progress:
Cylinder, Piston and Connecting rod reworked - need to add nuts and bolts.
Starting to make the geometry of the cylinder head.
I plan to make a as much as possible detailed engine replica 
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Lovely!
I always thought “boxer” referred to the symmetric motion of opposite pistons, not their angle.
I have no idea, although I was once able to set the ignition timing of my 2CV that had a “boxer” engine.
In my youth I rebuilt several VW beetle engines, which were boxer, and I think it obtained balance by having opposite pistons move opposite to each other.
Now that I think about it, it must have been the same in the 2CV as both cylinders ignited simultaneously so to set them was rather simple.
There are also “flat-twelve” engines like the one in Ferrari Testarossa.