Liberty exhaust ports were evenly spaced. Going by the J.A P on the side of the car, I'd guess it's a J. A. Prestwich engine used in aircraft and dirigibles. That British company was better known for its motorcycle engines.
This is the good S/S spring. See how the second leaf extends pretty well to the rear spring eye? The right side 454 second leaf does not do this, ending about where the third leaf in this spring ends. This allows the 454 spring to sag in this area. I use 455's on both sides on my cars.
UM......Yeh, NO..........jus' sayin'...........
