My favorite prospect for "liquid wood" gasoline replacement is a blend of methanol and turpentines. Though you can probably further process pyrolysis oil into lighter fractions by cracking it. Sometime I'm going to look into making a wood fueled gas convertor that works as a turpene and methanol distiller at the same time. So what happens is, you can start the car at the same time as you fire the converter on stored liquid fuel, drive 15 mins, then switch to converter gas output, drive on convertor gas output, and meanwhile it's distilling off methanol and turpenes for the next start. It would be nice if you could implement electronic control and fuel handling such that it's pretty much transparent in use. You can theoretically get this working on any organic materials, grass clippings, rags, old tires, etc.