True Ben,
Your original post mentioned 17 gallons = 65 liters and I assumed you would be thinking imperial gallons not US gallons, because the discussions on here always refer to the tank as being 18 gallons (obviously they mean Imperial gallons)
I made a spread sheet in which I enter 'liters used' and 'distance travelled in miles' and it converts to liters/100km, km/liters, MPG Imperial, MPG US, miles to KM, US gallons, IMP gallons.
It is very informative.
I always think in Imperial MPG for my 250SL and Km/liter for my Toyota Corolla.
Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL, auto