I plan to do a general re-conditioning of 2 old model cars - 1979 Toyota CORONA & 1984 Ford LASER. Not wanting to change Engines (but willing to modify - if need be), I intend to swift away from lead-free 100% Gasoline-Fuel to any low-cost technically-feasible Alternative Fuel recommendable. While only E10 (Gasoline-Ethanol Mix available in Gasoline Stations) and LPG are now used as CarFuel in the Philippines, would anyone have a better low-cost technically-feasible environmental-friendly idea? I would want to maintain the Outside and the Inside original configuration to the cars - but would entertain underchassis modification - if necessary.