Editing Quad 4 engine (section)

==Common features==
The Quad&nbsp;4 name is derived from the engine's four-cylinder, [[Multi-valve#Four valves|four valve-per-cylinder]] layout.<ref name="dl-jun2019"/> The engine has a [[cast iron]] [[Cylinder block|block]]. The [[Cylinder head|head]], camshaft carriers, and timing chain cover are aluminum, and the sump is die-cast aluminum.<ref name="jalopnik-mar2019"/>

Although [[toothed belt|cogged]] [[Timing belt (camshaft)|timing belt]]s were becoming popular among contemporary overhead cam designs, the Quad&nbsp;4 uses timing chains to drive both camshafts, as well as the water pump. Engine accessories are driven by a single-plane serpentine belt.<ref name="hrm-apr1987a"/>

Fuel is delivered by an electronic fuel injection system, and spark is produced by a distributorless ignition system called "direct-fire", that alternately fires two ignition coils located under the cast aluminum engine cover.<ref name="jalopnik-mar2019"/>