What octane fuel should I use - 318 engine?

[captainpine]

Since the 318 was designed for leaded fuel, what grade of unleaded gas do I need to use?

[Rickf1985]

A 72 318 will be a low compression motor so regular grade should suit it fine. If it pings any you might have to move up to mid grade but running anything higher than you need is just a waste of money.

[Rex]

I put non oxy premium in mine, but it sits more than it gets driven.