318 MAX fuel economy builds?
The magnum heads port window are a closer match to the regular performer intake size than the LA 318 or LA 360 heads. Both are in between the 318 and 360 size ports.
The stock magnum rockers are not adjustable, but adjustable ones are not terribly expensive since a/m chevy rockers will work by installing a screw in conversion rocker stud in the magnum head.