(06-01-2014, 04:04 PM)Ruan Wrote: See I had an idea of bodging it badly... This was only a wild thought, use a coolant temperature map - since I know they're able to adjust SOI - if you had a switch that could near enough short out the sensor (or known value resistor...) and having it at that temperature read by the sensor - you could then modify the SOI to be very late at that (fake) ect.... Then if you can switch injector calibrations (NO idea if you can do it on the fly) - or at least force it to an area never reached under normal conditions to get the fuel in late... But the thing is, that's not doing it in multiple stages, that just allows you to throw fuel in very late in one hit, you still want a proper normal combustion, but just dropping fuel in later into the cycle when requested... You want to be able to do it as a post injection really...
There's got to be a way of enabling the post injection maps, therefore you have adjustable quantity and soi for them without pissing with calibrations? Surely?
Firstly, yes you can adjust injector calibration maps on the fly (it actually does it out of the box anyway, based on requested SOI (based itself on requested IQ/rpm etc). That's how it works out it's whole concept of injector duration.
Your theory is sort of what I meant anyway - but without a switch... use the vehicle speed as a switch. Which there IS a map for. You'd just have to make sure that when stationary, with foot to the floor, the situation it was in could NEVER be reached under driving conditions.
I've just been looking now, and following through how the ECU comes to a concept of "time" and how it then works out all parameters for a particular injection cycle and it could be done - but as I say, would be a lot of arsing about / redoing axis on maps, fudging which maps it uses and stuff.
JP
oh, and while I think on... the normal injector calibration maps DO allow for post injection too.. they are based on crank angle anyway.
JP