15-07-2021, 01:22 AM
(This post was last modified: 15-07-2021, 01:34 AM by Tony Griffiths.)
I just buy whichever is cheaper and from the station nearest to where the car is about to run out. I never bother about the brand, nor do I add anything to it. Lead substitutes are unnecessary; Sevens were running for years before leaded fuel was introduced - and this was sold as a means of preventing "knocking" and, as a side benefit, reducing valve seat wear, neither of which troubles an A7 engine. I cannot detect any performance difference at all between any of the fuels. With its low compression ratio, I understand that a Seven can, when warmed up, even be persuaded to run (illegally) on paraffin - especially with a 24T2 carb fitted with an adjustable main jet.