As I recall, the camelhumps had larger ports and valves than standard. The 275, 300 and 350 horse 327 engines used the 1.94 intake valves, and the injection motors had 2.02 intakes, though the bigger difference was actually in the exhaust valves. It was the same casting, so you could cut the valve seats in a 1.94 head, and put the larger valves in, to end up with "fuelie heads.