Food for thought, I have a 98 GU TI duel fuel and I wanted to fit a duel battery so I chucked out all the factory air box and shit and made a s/s 3" snorkle with a scoop across the top of the windscreen that has a narrow panel filter in it (the same as the ones used on V8 holden OTR intakes) and now I get a lot better fuel ecconomy on petrol but on gas it stalls every time I back off the throttle to coast up to a corner. I put a vac/pressure diagnosic gauge on the intake duct next to the gas mixer and at 30km/hr with my foot off the go pedal it was showing +0.12 bar and I think that pressure is upsetting the LPG flow.