Originally Posted by
engineermike
I’ve played with gdi injection timing (4-stroke) on the dyno. With an arbitrary piston and injector design, the power goes to complete crap at high rpm when I ended fuel injection later than about 125 deg btdc on the compression stroke. 2-strokes can’t start injecting until the exhaust port closes, let alone end it, meaning injection timing is MUCH later than anything I did. This just goes to show how absolutely critical the spray pattern, piston geometry, and spark plug location are on a DI 2-stroke.