Editing Cylinder head (section)

====Overhead camshaft (OHC) engines ====
An [[Overhead camshaft engine|overhead camshaft]] (OHC) engine locates the camshaft(s) in the cylinder head above the combustion chamber. Eliminating pushrods lessens valvetrain inertia and provides space for optimized port designs, both providing increased power potential.

In a [[Overhead camshaft engine#Single_overhead_camshaft_(SOHC)|single overhead camshaft]] (SOHC) engine, the camshaft may be seated centrally between valve rows, or directly above a single row of valves (replacing rocker arm actuation with [[Tappet#Overhead cam engines|tappets]]). SOHC engines were widely from the 1960s to 1990s. (eliminating pushrods but still utilizing rocker arms)

[[Overhead camshaft engine#Double_overhead_camshaft_(DOHC)|Double overhead camshaft]] (DOHC) engines seat a camshaft directly above each row of offset valves (intakes inboard, exhausts outboard).<ref>{{cite web |title=FORD DuraTec Engine 3D Simulation(18) - Dailymotion Video |url=https://www.dailymotion.com/video/xaafuy_ford-duratec-engine-3d-simulation-1_tech |website=www.dailymotion.com |access-date=27 March 2022 |language=en |date=27 August 2009}}</ref>  DOHC designs allow optimal [[crossflow cylinder head|crossflow]] positioning of valves to provide higher-[[RPM]] operation. They are typically larger in size (especially width) than equivalent OHV or SOHC engines. Even though more components raise production costs, DOHC engines seen widespread use in automobile engines since the 1990s.