A good ole ported 5.7 head with larger valves that flows less than a ported 6.1 made more hp/tq. Both engines were close in cubes. One a 418 and the other .005" over 419.5. Both had the same 9.5:1 compression, same name brand camshaft and lift except the 419 had 2*'s wider lsa. Same dyno, same operator, same fuel and timing curve and same tuner. Both these engines were built with a blower in mind.