f0s get a modern sequential injection lpg gas installation. Preferrably Prins VSI. This will give no loss in power, no more chance for backfire and yer car will only be 15-20% more thirsty when driving on lpg gas.
Vialle LPI is another good choice but they have never done research for our engine so there is no original kit for it.
Drakey probably had an old lpg installation. These are known to cause problems, u can feel the loss in power and the biggest problem of all is backfire wich can blow up ur manifold and cause serious engine damage.