I tried driving 1/8-1/4 throttle, 0-2500 rpm never over 80km max. Clear roads at night 5.4ltr
1/8-1/4 with some 1/2 , 0-3000rpm max up to 120km hot day with traffic 7.1ltr

Also, i tried 94petro.. Awful stuff. The btus are same or lower then 91 power and aki is to high.
In 5th i put full load from just under 100km at say 2500rpm
When it was climbing it aeemed sluggish, then as it hit 3500rpm ( open loop ) it hit a wall and wouldnt accel any more.

My assumption is: the higher aki is preventing full burning of the fuel, which has te same or less energy then 91 to begin with,
The result is, less power, less energy, more unburnt raw fuel, less mpg.

When the take was empty i used 91 vpower again and noticed that i did not exprience the same "wall" or sluggishness.

Now im going to try 10% pur toluene making 93.3 oct but with more btus ( thermal energy )