Good question! Dad used to use a 4" stroke 49-53 Mercury crankshaft, stroked out to 4 1/8", and bore the blocks 1/4" oversize to 3 7/16". To do that successfully, the two center cylinders had to be moved apart a little to keep from getting too close to the exhaust passage between them. Then he would grind the small end of the connecting rods a little to let the pistons center up in the offset cylinders. The next door neighbor to the guy who sold me the 216 engine in Townsend Tennessee has a complete 48 Furd 2 door sedan that belonged to his grandfather- - - - -hasn't been run in many years!
Jerry
