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