The 4.490 rough bore World cast iron wedge block I built several years ago had .039 restrictors in the oil passages to each head, They ended up flooding the B1 heads with single shaft roller rocker arms bad enough to cause over filling the heads issues on the dyno running the motor at 2500 RPM for extended periods while the dyno operator dinked around on the computer, both heads had two #8 AN drain back lines on both ends of the heads
I'm getting ready to build myself a Koleno high nickel cast iron block but I'm going to go to a set of paired shaft rocker arms EDITED on the B1-MC heads, not a single shaft set up so the oil passages to the heads won't be used