Cam question...

they might've half had a clue about what they were doing. or it's entirely possible that they were just using up what they had laying around.

"J heads" and "double roller" is keywords toward performance. though J heads could have either the big valves or regular size valves.
Right on.. and you're completely right about the half a clue thing.. because I know little to nothing about building an engine and automatically thought of "performance" because of the heads and dbl roller.