Rossko is assuming the throttle closes during gear change, which it doesn't.
The more I read about gas, the more I think the whole thing seems ... a bit of a bodge?
Then again, that's my general opinion on piggyback ECUs on top of OBD-II compliant ECUs in general (hence the standalone on the MR2) - you're always fighting the stock ECUs self-learning, it seems.
Well, yes and no. The alternative is a second dedicated ECU for LPG, of course, or a purpose designed Bi-Fuel ECU.
The bodge then becomes making the new ECU work with all the other systems in the car, so CAN comms, both standard and proprietary to Bosch with the ABC/TC, autobox and the various other signals to the MID, instuments, climate control, etc.
With a "piggy back" ECU you have a nice simple interface to hook up to; a pulse for each cylinder with duration proportional to fuel demand. In theory, as long as you apply the corrections to compensate for temperature and pressure of the LPG the "learning" mechanisms in the main ECU work to your favour on LPG too.
The only slight issue you then have is that the ignition map is set up for petrol where ideally you'd want a little more advance on LPG and the transient corrections assume a liquid fuel and "wall wetting", which is not the case with LPG.
I suspect the second of the above is a factor in this lag we are seeing.
So, a bodge? Perhaps, but between a rock and a hard place. :-/
Kevin
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Topic: Stag LPG kit supplier...? (Read 4455 times)