A2Steve
A2OC Donor
I doubt this. I switched from 95RON petrol around three years ago, and there was no change whatever in my closely monitored economy or the performance.
High octane equals better mpg | Autocar
99-octane fuel proves more efficient than regular unleaded
www.autocar.co.uk
Perhaps on a 75bhp 4 cyl it doesn't make enough of a difference