I own a 1962 Hillman Minx, which is a beautiful car and I love it. What is the best fuel to use in her as she did require super petrol? I have been told I could use Optimax or any other premium unleaded. Do I need an additive such as Valvemaster?
Your Hillman's engine had a compression ratio of 8.3:1 when new, and the factory recommended that it was run on fuel with an octane rating of at least 97. On that basis the fuel to use now is premium unleaded, which has an octane rating of 96. Use an additive such as Valvemaster, available at your local servo.