Hmmmm, got impatient today...
Went to pick up a supercharger coupler from these guys:http://www.powerhouseautomotive.co.uk/c ... rades.html
Who weren't in. So I chucked five quids worth of LPG in, had a goodly sniff about, then brimmed the tank. Took 75L from fully empty - close enough to the 80% on a 95L tank for LPG pump accuracy purposes, in spite of the tank angle.
Popped back to their unit and had a play with the LPG system. Laptop in, autocal run with one injector to energise the solenoid valves. Whoops. That union on the rear reducer would be fingertight then...
One borrowed "special tool" from a nearby industrial unit (1/4" whitworth open ender, sides ground down, head bent to 70 degrees, and handle cut short...) and that was nipped up and after 20 minutes of sniffing/autocal all was declared good. On a still day I dare say there's no need for the leak detector - that tracer they put in the gas absolutely mongs in the slightest concentration.
That's about as far as I got before the Powerhouse owner Lawson turned up.
"Err, WTF are you doing on my... ...Oh! Cool!" Cue a 2 hr chat, buying the supercharger coupler, and me sat in the corner of his yard playing for the rest of the afternoon.
Job zero - "fix" the part load breather leak with enough tape to let me play with the LPG kit.
Job one - switch the wiring from voltage based lambda to current based UEGO.
Job two - set up the vapourisers. Easy enough one at a time as described. Clockwise to REDUCE the pressure is the opposite of what I thought. Initially set to 1 bar. (the readout on the Stag software is the differential pressure, not absolute, so you set it to 1 bar not 1 bar above manifold pressure)
Job 3 - autocal. Hmmm, it does 1, then 1/3/5/7, then all 8. Big regular miss, injectors too small, multiplier 2. Turn 1 bank onto gas injectors and "go manual" - adjusting the vapouriser pressure and multiplier manually until the gas injection times are little more than the petrol ones. Settled for 1.3 bar and a multiplier of 1.4 at first. Switch all to gas, and we have a wooden leg on our caterpillar...
Regular miss. Switch them individually and there's something up with #5 gas injector - regular miss. Oh well. Let's play with the other 7 for now and leave that on petrol. Actually no, let's play with the "good LPG bank" and leave the other bank on petrol as an injector time comparison. (both banks have near as dammit identical fuel trims on petrol)Observations
Cold-start on petrol gives 7 ms pulsewidths. These rapidly drop to 3.5 ms.
Idle on petrol in Park gives 2.5 ms pulsewidths. 3 ms when idling with the autobox in "D" or "R" positions.
Fast idle on petrol (2000 rpm) in Park gives 2 ms pulsewidths.
Against the brakes in D, 90 kPa MAP at 2,500-3,000 rpm is a petrol pulsewidth of 8 ms. Not a lot?
The UEGO/wideband/current sensor reads "around about 2.1 units" in the Stag software, whatever those units are. "Very rich" is 2.5 units. "Very lean" approaches 0.5 units.
Reducers generally sit at 80-85C, gas at 60-70C at low demand.
Tickover in Park is 640 rpm; 600 rpm in D/R. Quite low, but steady as a rock.
Cold start enrichment is huge! It disappears pretty quickly though.
I think these petrol injectors are much bigger than the 440 cc suggested, or the engine is a lot more efficient than my crude spreadsheet assumed - 2 milliseconds is a low pulsewidth at fast idle, no?
If you crank the multiplier hard then the petrol ECU will adapt by up to +/- 20% without throwing an OBD code. Throwing in 50% more gas than it needs makes it a little "fluffy" at idle but it doesn't object, so it should switch over happily before the full warmup cycle is complete.
Spun back through town and took a look at the petrol map that the ECU collected thus far. It'll need a lot of road to populate that even without the supercharger.
Will take a look at that #5 tomorrow when the engine isn't at 100C. Good job it's that one as it's only one of two where you can get to both ends of the pipe, what with the spud being on the front side of the charge cooler. I'm thinking either duff from new (unlikely; seems to tick), debris inside the injector (hope not; I did try not to), or a piece of hose/debris inside the spud (hopefully). The HANA outlet stubs aren't the easiest to push the pipe over and I think I could have "cut" a piece of the rubber pipe off with the end of the injector when fitting it. Well, I hope that's it anyhow!
Not too expensive if the injector is toast/I've gunged it up, but it's more wait time:http://translate.google.com/translate?c ... pair=pl|en
Glad that they're readily swapped without removing engine bits? Oh yes.
Oh, and 33 ohms works a treat for preventing the petrol injectors from opening, triggering the gas ECU, and not setting an injector fault code on the Jaguar. I swapped the resistors inside the ECU rather than running the separate emulators, as it saved mounting yet another box and yet more wires.