#4448308 heads have any potential?

they are IMO the best LA head you can use. The earlier heads have a decent intake port but the exh sucks. The 308s use the exh port the Magnum heads were developed from. I run larger intakes because a new bigger valve is the same cost and the seat angle can be brought up and out to the edge of the factory seat. Bowl blend and gasket match the intake side. Remove the AIR bump, enlarge the exh by about .060 on the sides and roof, and blend that back without touching the port floor. Then tap the AIR holes at the flange and use red locktite tp seat grub screws in the holes.