I got 37mpg on my first tank and have never gotten less than 34mpg (even after the install of the JCW engine kit). I only drive my Clubman on the highway, but I can't even imagine getting less than 30mpg anytime.

 

Then there are those who point out that engines are the most economical when running at steady-state cruise, and that the more time spent getting up to speed, the more fuel is used. Meaning, that brisk acceleration up to cruise is more economical, since less time is spent in acceleration mode.

To each his own! I fall into the "brisk acceleration" camp.

Spridget

 

I average between 28 and 30 on regular with almost no highway miles. Driving to and from work is bout 20 miles of country type roads, not highway but not stop and go either. If I do a lot of short trips running my kids around my mileage definitely drops, but usually to about 28. Using manually computed method.

I haven't had a chance to really go an a long highway trip, but the short runs I have done, using the OnBoard metrics I get around 38-40.

 

So the on-board MPG calculator is inaccurate?

I have a 2011 MCS. It used to be in the 30s, but that includes some freeway miles. I've reset it to calculate my city driving only. After 200~, I read 23.~ MPG. That's not in sport mode, just normal driving, shifting at 3k~. Once in while I would get enthusiastic, shift at 4k~ and accelerate quickly.

Would it matter if we skip 3rd and 4th and jumped to 5th or 6th? (Ooh, that sounds kinda dumb. Bracing for some flaming... )

 

I believe that the on-board calculator is inaccurate because it is nowhere close to what I get with my calculations.

 

On my 2009 cooper S I noticed that the the computer was typically ~2 mpg higher than the actual consumption

 

No, that's not dumb. In fact, that is how most people in Europe, being more mpg conscious, drive.

 

2011 MCS just past break-in mileage. 75% highway, split between 65 and 75 mph. Hand calculations thus far on all three fills have been between 33 and 34 mpg. On-board computer says 33.3 mpg. I'm happy.