electronic means suitable for causing the spark in the spark plug in each cylinder whose piston is located near {HEAD ~ a top dead centre} as identified by {TAIL ~ a sensor} placed on a crank shaft 
as identified by
electronic means suitable for causing the spark in the spark plug in each cylinder whose piston is located near { HEAD ~ a top dead centre } as identified by { TAIL ~ a sensor } placed on a crank shaft
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH