93 2.4 (2L-TE) Fuel Economy??? PLZ Help

[aadi.eire]

Hi, I have a 93 2.4 surf with a 2L-TE engine. How many miles or km I should get in a full tank? or How many in a litre? These surfs comes in a 55,65 and 75 litre fuel tanks: is this true?

Any suggestions on increasing the fuel economy?

Thanks