[digs latest petrol receipt from wallet]
My usual fill up in a Mk2 is about £50, and for that you get about 250 miles. If you press 'info' on the nav and then 'trip information' it gives you avarage MPG since reset and distance left in tank. I always fill it once it is showing less than 20 miles and it takes about 60-65 litres. Therefore the reserve is about 10 litres, or 2 gallons, or 40 miles. Don't like playing Petrol Bingo so I have not filled more than 67 litres.
Does this help?
John