[gordon]

As I understand it, virtually all of our trucks will run on any of these fuel types without engine damage. In particular Dodge flatheads were based on a 1930's design that would run on fuel before they thought to start putting TEL in it, so no engine problems as such unless you are working it hard and revving it hard - not our thing really. Extra cost you will just have to put up with.

You will have problems with pump diaphragm, hose linings, tank sender gaskets, and so on, as the more aggressive fuel will just eat away at them. You should be able to source new reproduction hoses that will put up with it though. Don't forget the fuel filter top seals, as those have to work for the fuel to draw through. Most carb gaskets materials will be affected less as there was no 'rubber' in them to start with.