Quote
Chevrolet '42 thru '47 manual
The engine used in all 1942 passenger cars and trucks is a six-cylinder, valve-in-head type. The regular production engine for passenger cars and all trucks has a displacement of 216.5 cubic inches, using a 3-1/2" bore and 3-3/4" stroke. For 1-1/2-ton trucks only a heavy duty optional engine is avail­able. This engine has a displacement of 235.5 cubic inches using a 3-9/16" bore and 3-15/16" stroke.

[b]All parts of the two engines are interchangeable with exception of the following parts Cylinder block and Crankcase, crankshaft, camshaft, pistons and pins, all piston rings, oil pump screen cover support, oil pan pipe assembly, oil pan, oil dis­tributor to valve rocker shaft pipe, valve lifters and push rods.
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I didn't think there were any significant changes to the 216 or 235 untill they went "full pressure".. so my SWAG (systamatic, Wild [censored] Guess) would be that so long as your engines arent full pressure, it outta work.. and even then it still might.

an idea is only stupid if you think about it rationally.