rob1miles said:

I think there was a lot of misinfomration around when unleaded came in and fear stories that lead to the idea that a lot of valve seats would pocket. At the time I was running BSA motorcyles with manual advance and retard and iron heads. They were designed for pool petrol (68 octane) and I looked the reges up on the DVLA and some are still shown as MOTed, now haveing run 70 years. I can't remember anyone who sent their car head off to get it modded, I was driiving Truimph Heralds at the time and we all just retarded the timing 6deg. If the engine lasted 6 years more that was 3x as long as the chassis did! Petrol additive is not a bad thing, and it keeps things clean and lubed, I've always been a fan of Redex upper cylinder lubricant, it really keeps the carbon deposits down (they stay soft and burn) and stops it causing detonation but I'd probably only put a dose in every 3 or 4 tanks full. Even unleaded is better than a lot of petrol was when Series landies were first running.
https://api.parliament.uk/historic-hansard/commons/1950/nov/13/pool-petrol-standard

Click to expand...

rob1miles said:

I think there was a lot of misinfomration around when unleaded came in and fear stories that lead to the idea that a lot of valve seats would pocket. At the time I was running BSA motorcyles with manual advance and retard and iron heads. They were designed for pool petrol (68 octane) and I looked the reges up on the DVLA and some are still shown as MOTed, now haveing run 70 years. I can't remember anyone who sent their car head off to get it modded, I was driiving Truimph Heralds at the time and we all just retarded the timing 6deg. If the engine lasted 6 years more that was 3x as long as the chassis did! Petrol additive is not a bad thing, and it keeps things clean and lubed, I've always been a fan of Redex upper cylinder lubricant, it really keeps the carbon deposits down (they stay soft and burn) and stops it causing detonation but I'd probably only put a dose in every 3 or 4 tanks full. Even unleaded is better than a lot of petrol was when Series landies were first running.
https://api.parliament.uk/historic-hansard/commons/1950/nov/13/pool-petrol-standard

Click to expand...