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Lurker, why does the pressure stroke need to occur when all injectors are closed?
The pump timing doesn't seem to have (or need) a direct relationship to injection timing.
My guess is: based on the Tq_requested vs Ne table, there is a target rail pressure that dictates the total on-time of the spill control valve (note: the timing at which the valve is energized remains constant, while the timing at which the valve is de-energized varies to control the fuel delivery volume). I would think this is a closed loop system, where a pressure sensor on the rail sends current rail pressure info to ECU, which compares this to the target fuel pressure based on Tq_requested and Ne. If current rail pressure is lower than target fuel pressure, extend the spill control valve on-time. Then read current rail pressure again and this becomes a repeating feedback, response, feedback, response, etc. loop.
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