What fuel is best to use?

[Bruce Parker (RIP)]

Highest octane you can get as it is usually is the only one that doesn't contain any ethanol, but check to make sure. Ethanol softens the old rubber in your fuel pump and hoses. Then always keep the gas in the tank for no more than 4-5 months because any longer and it tuns to an un-burnable turpentine that will also clog your carburetor. I've been told gas stabilizer intended to lengthen the life of ethanol blends won't work on non-ethanol 'high test' so keeping it fresh is your best bet.

The lead substitute is meant as a lubricant for regular, non-hardened valves (which most CMPs are either because they are original or rebuilt that way). I don't use it but probably would if I drove my vehicles more.