Corsairdeluxe - 4 cyl Not a 1938 design but a 1928! As such it should be compared to the Model A Ford engine. Barney Roos did refine the design in the late 1930s, but it still has ridiculously long conn rods.
The 4 cyl parts are still easy to find while the 6 cylinder parts aren't. How hard are you going to drive it?