I had a similar query but running the gti on bioethanol as opposed to LPG. Still looking for an answer - emailed VW in germany a while back and they said their diesel engines run on biodiesel, but there is no provision yet for their petrol engines to run on bioethanol. It would be excellent though, as there is quite a substantial increase in power, reduction in CO2 and it costs much less, although it is very slightly less economical. Having said that, I did get an email from a company who does conversions for bioethanol, and he said that it is doable on the golf.