All is basically going well right now (must be constantly vigilant in war with the dreaded breakdown) but when I checked oil level I was 2 quarts low. It doesn't smoke at all and I couldn' t find any on the ground.... Where does it go??
Three possibilities, your oil pressure sending unit could be leaking or your fuel pump if it's the mechanical one on the head. The fuel pump has a pressure equalizer hole in it, if the diaphram shaft seal is shot it will blow oil out while running as will the sending unit. I would expect to see some oil on the bottom of the car but you would be loosing most of it while driving. Also you could be pumping it into the cooling system, check the rad for oil in the coolant, It seems unlikely that you could hide 2 litres of oil in the rad without coolant leaking out and showing up on the ground but again it would do most of the leaking while running. How fast does the 2 litres disappear?
Check your PCV system. If PCV valve is stuck you will be building up pressure in the block and pumping oil.
Same happens when you have a vacuum leak. Check for vacuum leaks everywhere, including front and rear engine seals, even dip stick!
I havea 280C here (yeah that is not a typo.... it is a C big 4 door thing, anyway....) It has an L28 that losses oil quickly.... none on the ground, doesnt seem to burn it when running in the driveway.
BUT. when my wife was driving it, and i was behind in the 260, it blows smoke when you put your foot down....