Hello ! As is well known, a petrol engine ignites by means of a spark plug, a diesel by compression on its own. In addition to ignition time (for petrol engines) you will always find the same information: – Late ignition: some degrees before OT – to start – Early ignition: much more degree before OT The background is that the combustion and the combustion pressure last about 20ms (?) long and only 1ms after the ignition spark occurs. Logically this should take place during the downward movement of the piston. Eight said, is ignited with increasing speed all the earlier, so that the combustion pressure remains at the same crankshaft position. As far as – so clear. But when does a diesel ignite ? Normally, if the diesel-air mixture is compressed enough. That means always just before OT. Worst case in OT. With injector engines also something can be controlled by the injection time – also the self-ignition time ? Here I ask for your knowledge. Greetings !