Question

What are the difference between valve timing and injection timing?​

Answer 1

• Valve timing

In a piston engine, the valve timing is the precise timing of the opening and closing of the valves. In an internal combustion engine those are usually poppet valves and in a steam engine they are usually slide valves or piston valves.

• injection timing

Injector commonly refers to the nozzle holder and nozzle assembly. Start of injection (SOI) or injection timing is the time at which injection of fuel into the combustion chamber begins. It is usually expressed in crank angle degrees (CAD) relative to TDC of the compression stroke.