by nexus665 » Sun Dec 09, 2012 4:25 pm
Hi,
sorry, haven't had much time lately, this information should be relatively correct - it's taken from a Bosch publication describing the VP37 and its applications (different plunger pistons and fuel volumes that can be delivered).
That means, even if your pump voltage map goes that high, it won't be able to deliver 65mg/stroke with a 10mm plunger piston, no matter what size your nozzles are - there, the piston size is your limiting factor.
~57-58 mg/stroke is about what it can do with 10mm and large nozzles, max. With smaller nozzles, leakage losses are higher, leading to less max injectable fuel (~51mg/stroke for the .184 stock nozzles, for example). It can't go higher than that because the 10mm plunger piston only has a specific volume it can deliver - this is not adjustable other than switching to a larger piston.
Well, not strictly true - these values are fuel-temperature dependent and are calculated for 30°C fuel temp if I remember correctly (just search for diesel density and calculate it yourself from mm³ ;)). So if you cool your fuel down somehow, you can inject a little bit more (same volume, more mass - fuel density is higher when it's cold), but 65 is too much IMO.
The factor for the MAP linearisation axis (mV from MAP sensor) is 4.878049.
Regards