Well I was told that it couldn't be done in a MCS, but I've done it! On my home from the Dragon yesterday I gassed up in southern KY and drove 300 miles to Bowling Green OH where I topped it off. My OBC said 42.2 but I never go by that and always use the calculator and came up with 40.7 mpg. I had the cruise set anywhere from 65-75 mph FWIW. Now I did turn off the "sport" button at about 40 miles out and it almost went up right away. My projected miles at one point was 600, but went down a bit.


The car was awesome on the Dragon, but that's for another post with pics but I must say this car never ceases to amaze me

 

I got 39.22 from Mt. Princeton, CO to Moab, UT with an automatic.
And I was passing Jeeps like crazy....
But I was in the flow and not racing; very impressive little rocket.

BTW, I compared the ODO to the GPS and found that the car under-reports the actual mileage. So your mpg's are even better.
It's about .8% difference with stock 16" wheels/runflats.

 

That is awesome guys.... the best I've gotten is 35 MPG w/ Autobox.

 

first highway drive to work today - car is three days old. Average said 44.5 mpg when I exited the highway. With the extra few miles to get from the highway to work it dropped to 41.5mpg.

 

Was it downhill all the way?

 

I got 32 mpg out of my 2006 MCS once. I had to drive it like a little old lady... never over 2000 RPM. Early shifting at every opportunity. 55 MPH top speed on the highway. No AC - No open windows - only vent.

I got sick of that real quick, but I made it for tank of gas.

Over 40 mpg is incredible!

 

The OP did it in a MCS over 300 miles - which is very impressive.

I can get the calculator to read over 60 if I measure just one trip into town. I don't think you can use a short trip to get any accuracy for average mpg.

 

My trip to work is 37 miles, mostly highway. I wasn't referring to instantaneous mileage but average over the trip.

 

Could be with a tailwind. It makes a big difference.

 

I agree. You have to check gas mileage based on a tank of gas or at least close to it. The car always gives a higher reading than what you really get. At least it's been that way for my first 3 tanks of gas.

 

Congrats Roger on the great mileage and making it back safely from the Dragon. The R56 certainly is an awesome feat of torque and economy!

 

My MCS 6speed has averaged that on all tanks since new (4500 miles now). I calculate the same way, and dont rely soley upon the OBC. I see a 0.6 mpg diff if I take the back roads versus the highway to work.
Back roads = 30 mile commute 42mph avg (number of stop signs, and lots of fun 90 deg corners)
highway = 18.9 mile commute (1.2 mile city/ 17.7mile highway) 43.7mph avg

 

i'm here to bring down the average. I have fun on everydrive.

 

FWIW I got 36.5 going down there and no, it wasn't downhill going back I'm sure there's something to letting go almost empty and next time I'll look into doing just that. Considering the car is rated at 36 hwy its not surprising to get 40 if you think about it, look at the other ratings for mpg on your window sticker and you'l see what I mean, its in much smaller print, but its there. Another thing that helps, but only a little, is making sure your tires are properly inflated as well, or in my case with going to the Dragon, I ran 43psi in the front and 40psi in the rear and never changed it. In closing if the hp/torque can be underated why not the mileage too

 

This is really awesome news. Upon returning from Iraq I plan on driving to Virginia beach to pick up my Mini. Then a 200 mile trip to NC. From there a few days later it's like 900 miles to Chicago for a few days, then to Ohio, then back to NC so the better the mileage the better. I'll keep a log if I remember.

 

I got somewhere around 42 on our trip to Topeka (650 miles). Filled up in Austin, then at ~ 180 miles in Dallas (last stop with 93 Octane). Drove the rest of the way to Topeka (470 mi) and read 70 miles to go. (we went racing in Topeka so I couldn't fill it up for an actual calculation, but I estimate 470mi/11gal.) I was drafting behind a travel trailer, so I think that helped. But I didn't use cruise control.

 

Great MPG numbers

 

A trip to Chicago is coming up in 2 weeks, but this time it will be all four of us in the car. I'll do the running the tank pretty close to empty and see what I get