Thanks Philip. I think I switch to 98 for a while and listen carefully. I drive the Morgan since 1996 and it was the first time this year in the UK (TOTH) that I thought to hear some knocking on mid-revs, uphill, but I'm not 100% sure about that. It's always serviced by a very reliable Morgan agent and there are no alterations, except a sport exhaust, but that mod was already done already 20 years ago!
I never used the biofuel mixes that you can get in Germany (I live close to the border), because I'm afraid for the old fashioned tubing, etc.
So with our mileage it's just spending a few euros more.
