Neptune, i've noticed petrol owners only talk about L/100K maybe i need to take one of them 100k from nowhere drain there tank give them the L they claim to use in 100k & see if they have to walk
Well i don't know what distance you could expect, as only petrol i drive now is a Harley Davidson & a Toyota Hi Ace van the van is auto, i have a fleet card so can use premium if i choose. i have used BP 98 and BP E10 SHell V-Power Shell E10 i think i saw a very slight gain in economy with the BP98 in the Van. with the bike i always use BP98 as its very high compression & carb.
what i would do is fill the tank to the very top, can be hard with a new petrol car as that flap makes it harder but a trick is wait till fuel at the very top, then rock your car from side to side wait see if it has air pockets, if it has bubbles will come up and you can put more fuel in till its full as it goes. then you need to drive as petrol will expand, diesel does not expand as much. but the more fuel you can get into the tank the further you could drive on one tank. i would expect a car like an i30 with a 2.0L auto trans i would expect to do 700k 750k on one tank in country if i was limiting speed to 90KPH, but with hills can let it go slower than 90 up hill and faster than 90 down hill, just try not to kick back a gear, see how you go let us know.