{HEAD ~ A cam plane} is defined perpendicular to {TAIL ~ the longitudinal axis} and disposed between the open ends of the cylinders and a second end of the engine housing 
{ HEAD ~ A cam plane } is defined perpendicular to { TAIL ~ the longitudinal axis } and disposed between the open ends of the cylinders and a second end of the engine housing
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH