Cylinder head 15 may be made of {HEAD ~ aluminum} or {TAIL ~ steel} in the normal manner 
Cylinder head 15 may be made of { HEAD ~ aluminum } or { TAIL ~ steel } in the normal manner
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH