This head is one of 5 or 6 produced in the 1950s by Howard Johansen. I currently have one in my shop (however mine has a combustion chamber). It is an improvement to the Wayne GMC head since it has a 45 degree intake shelf vs the Wayne 90 degree shelf. The head was designed to take the original GMC rocker arm assy.
Howards design was used by Nick Arias in the 1990s when he reproduced this head. The head was marketed as the Howard/Arias GMC 12 port. At the time Nick was selling intake and exhaust assys along with roller rockers.
This particular head has a been raced at Bonneville and has set multiple records. I feel the reason the head has not sold is because there are better designed heads available today (Skinner, and the Ferguson Wayne). Also early GMC 12 port heads were known to have porosity issues....todays alloys are significantly better.
