"Same heads, cam, carb, headers, gears, vert, etc." All these thing will work different with different displacements, rod ratio's, torque, rpm etc.. so it could these part's we're just more suited to the 418.
maybe, but frankly I think the 10 to 1 360 ran better for what It was than the 418. 11.26 at 118 + is gettin it in a 3350 pound car
So if anything, the 418 underachieved, not the 360
