First fuel consumption calculated

136 miles on 19.36 litres = 4.26 gallons = 31.93 mpg

This was all gentle driving never above 60 mph and very little traffic hold ups.

The fuel gague was showing 48% before filling, so the capacity must be somewhere about 40 litres.

Equals 8,8 L/100km (gallon is a very strange measurement over here...especially combined with miles ). I guess that figure is what you can expect from a close to two-litre V2. Maybe it will lower a little bit after running in? Still much fun for the expensive drops

26.6MPG when converting to US gallons. That is certainly a lot lower than I had been expecting. As M3W mentioned though, typically fuel economy increases as the engine breaks in a bit. Still, for gentle driving, that doesnt sound great. What grade of fuel did you use? Is there ethanol added to your fuel as there is in the US?

The handbook says 55 liter tank, most recent digital flyer on the MMC website says 42 liter tank, Mogwires link to (un)official stats says "FUEL TANK 42 Liters (10 Imp gallons)." The handbooks were printed some time in advance to present to customers upon delivery, and just like other statistics of this vehicle have been updated/changed, the MMC digital flyer is probably the most-recent correct information.

That's OK, not brilliant but OK!

However, I get the feeling that it drops off pretty rapidly when you press on!

I imagine it will get worse when we start to rev it out.
I'm running super unleaded, I think it would run better, it's an american engine and USA fuel is generally better than ours.