LPG stalls on start

[ClassicAU]

sorry to be putting up stupid threads, but its a slow day at work and i'm bored! :P
anyway, i was just wondering if there was any way at all that i can stop my car stalling when i start it up. if i am on gas, and i start it, the converter automatically starts on petrol, then switches to gas a few seconds later. but it usually stall when it does the switch. is there some sort of adjustment that can be made to the converter to stop this? i tryed one with the mixture, but that just helped it to stay on the second time i turn it over, and even if it does stay on, it almost chokes to death and takes a second or two to settle down. the only way i can get it to stay on is if i hold the revs up as soon as i start it, but i dont like to do this, especially when it is cold.
but i guess i am just being paranoid!

woops, just saw there was a dedicated area for LPG : guess this should be moved there then. sorry about that

[Clarke AV]

Increase the value of the capacitor in the timing circuit. Try doubling the value first and see if you get a bigger time difference. If you show me what the circuit looks like I could probably do the mod for you.