That is not a model A ford engine, it is the european Ford 10, a much smaller and lighter engine, the USA model A engine is heavier.
The pirated online plans at the site given are incomplete, and Roy Nerou who actualy redrew much of the original aircraft and supplies the plans has the permission of the original designers family, so please support him and do yourself a favour by contacting him for plans.
The photo is of a Ford Model C engine, a Carden conversion. It has less displacement-- coming from both a smaller bore and shorter stroke than the Model A Ford--
but the block of a Carden Ford has the same basic dimensions and more importantly the same weight, 145 pounds, as a Ford A or B as converted per Bernard Pietenpol's plans. (Without the later counter-weighted cranks which are all heavier and vary in weight.) The C also puts out less power, 31 hp vs 38 hp for an A and maybe as much as 52 hp for a fully tricked out twin plug, aluminum head, counter-weighted B (which is of course even heavier than a C).
The 'Merikan Ford carries more oil in a deeper pan, so some jiggling of the the radiator, or maybe the thrustline would be required. But the Walther engine has a much higher thrustline, so that should be completely do-able.
This makes sense. Because the Brits, in their love of being eccentric, and after running out of words to add superfluous "u"s to, decided to tax engines based on cylinder capacity. So ole Henry just had his minions make the cylinders smaller while using as many common parts as possible. The bottom line is that an A can be made to fit and come in at about the same weight. Of course, in another lovable eccentricity, the carb and exhaust are on the "wrong" side 'cause they needed to clear the steering shaft which was likewise on the "wrong" side, to make it easier to drive on the "wrong" side of the road

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Please post a link or address for the "legit" plans.
We bought our Air Camper and Sky Scout plans from Andrew
Pietenpol Aircraft Company – Official Pietenpol Air Camper | Wisconsin
Maybe a Chilton will be airplane #4 or #5...
