When I swapped engines I set up the mapping using 95 octane supermarket fuel so that the fuelling and in particular the ignition timing would be slightly on the conservative side. (BTW, my engine does not have any political allegiance.)
Don't ask me why but every so often I treat Mog to a tank of V-Power but I have no idea if it makes much difference.
Remember that the cold winter air will make the engine feel more responsive anyway, in particular on an EFI engine that can automatically compensate for the increased air density by giving the engine more fuel.
