I'm runninig 11.5 to 1 with Dove alluminum heads. I buy the best pump gas available (ussually 91 sometimes 92 rarely 93) and add Octane Booster & Fuel Stabilizer concentrate additative by Manhattan
Oil . A 4 fluid oz. bottle treats 60 gallons of gas at 1 increment per 5 gallons. It was recamended by the previous owner. If I could buy 93 it would be great but. I had more a problem with cam and lifters going flat. 14° of initial advance and 20° in the distributor.