I usually throw those heads in the iron pile. There are 2 different versions of it. Maybe 3.
1 BBL - 1BBL carb and single exhaust
2 BBL - 2 BBLcarb and dual exhaust
Not sure which one you have pictured.
Did notice the chambers are slightly different than a standard head. See how the chambers are tilted to the left and right? Regular heads have the chambers oriented straight.
Can you provide a better pic of just the chamber?
The casting is the same thickness as standard heads. The reason they fail so often is because of the extra casting near the partial exh manifold cast into the head. Thermal stretching causes the cracks.
