I read this last week about this. If an engine was designed to run on leaded fuel, after a few years of it running on leaded fuel, the seats and valves have been coated and will be protected for up to 10000 miles (in a car). But, if you have the chance to put in a bottle of lead substitute every 5 tanks of gas, this would not hurt. If it were mine, i would run unleaded with a lead substitute every once and a while, if when needed, have the heads redone with hardened seats. I am not sure if a higher octane gas would help. I am trying to research this for myself also.
I would upgrade the old points and cap with the new electronic ones for around $100.
I would upgrade the old points and cap with the new electronic ones for around $100.