[kingsway]

My car is a normally aspirated 1.9 VAG diesel and, according to my Ultraguage, I am seeing about 70-79 mpg (imp) at a constant 60mph, and about 65-70mpg (imp) at 70 mph. (The stats shown in my signature reflect the fact that my car is mostly driven by learner drivers, and not me)

Looking at the stats on this site, I am amazed how well these cars stack up against the so much more complex hybrids. The top scoring diesel also appears to have very few aero-mods. So, looks like vehicle choice, plus hyper-miling techniques are what really make the difference!

I've just realised - I don't recall seeing any mention of BMW diesels here. My guess is they they would do well generally, but especially at the higher sort of speeds you mention..?

I drove one for a few weeks, some time ago. It was easily as economical as the VAG cars at normal speeds - but I do recall, from a short blast down an unlimited autobahn in a 3 series SE Touring wagon, that at 140 mph, you could almost see the needle of the fuel gauge moving towards 'E!'! (at the odd moment when I dared take my eyes off the road ahead!)