[Max Well]

Originally Posted by lbjgh

I don't think eco pro makes any difference on the highway... I just did a family trip to DC... fully loaded with 4 adults my 35i got 8.8L/100km (26.7 us mpg - 32.1 uk mpg) to DC and 9.4L/100km (25 us mpg - 30uk mpg) from Baltimore. (about 1000km each way). Average speeds were 62.1 mph there and 59.6 mph return. ...

If a few could share some data (as found in the 'Horsepower and Speed' thread), graphs could be obtained using Eco Pro vs standard, but it would also be helpful to have even the basic 28i and diesel engine curves from which to compare. Based on the 35i curve, I could almost have estimated what your average speed was during that trip. But it is more complex than that.

The difficulty (with comparing what kind of MPG numbers one can achieve in a set vehicle model) resides in the fact that so many variables go into the final equation. Grade of road (up or down in elevation). Average constant speed (which was provided here). Total load (which was provided here, although weight of four adults was not). Elevation (which affects air density). Aggressive passing maneuvers...

So while it is interesting to see what kind of numbers others can obtain, it remains an observation which is difficult to translate to how others can achieve such. If we, as an enthusiast community, can develop our curves, then they do speak for themselves (depending on the accuracy and precision of the graphs we derive).

I just got back from a 306 mile trip today - 265 miles of which was Interstate travel. Cruise set at 78 MPH. MPG was 24.7 (pure Interstate miles). Two adults (300 lbs), almost no load (except full tank at start, less than 1/4 at final).

[mindanalyzer]

I tried this experiment and milked an extra 9 miles for a tank (93 oct in hot miami fl) in eco mode. That is roughly equiv to 1/2 gallon ($1.60 or so), so no more Eco mode for me.

From now on Comfort and sport, not necessarily in this order

[rcblackwell]

Originally Posted by The X Men

I find that I can pretty much get the same MPG in comfort mode as Eco Pro mode if I just go gentle on the accelerator.

Having just returned from a 4200 km vacation road trip where Eco-Pro was used 90% of the time, I must concur. With Eco-Pro engaged and cruise set to 105 km/hr there was less than a 10km gain on a full tank of fuel (Diesel)

[Andy_o]

I must admit that the whole Eco pro thing has me perplexed

It may be that my normal commute is too hilly for me to gain the best out of it but I have found no discernible advantage using it as I seem to get broadly similar mpg using both Eco and comfort mode

I think that on the uphill stretches it may be using more fuel as it accelerates slower and seems to need more gas to get it up the hills

Or maybe it's my imagination !

Either way I can't say I've noticed any difference in consumption

I also find that I get better mpg using comfort without cruise rather than Eco and cruise .. But I reckon that is because the human can modulate the speed better than the machine

Yup I'm a driving God ! .. Not

Oh yeah and I'm in Ireland at the mo and just filled up for euro 1.23 a litre which is 87 pence sterling .., so sport mode all the way

[FSociety]

the most i've seen was 83mi gained and typically i see 40-60mi

[Andy_o]

Just come back from a 1200 mile round trip

Part of this involved a trip across Ireland and back

On the way I did Eco pro and used cruise as/when possible .. I averaged 38.8 mpg

On the way back I kept the car in normal/sport and didn't use cruise control I averaged 41.9 mpg

But traveled at same speeds with the same loads etc

Same route used both ways and all done under lab conditions !! ( not )

So my experience is that Eco pro uses (may) more fuel than comfort mode or maybe not !

Distance travelled approx 160 miles each direction

[Ranger 6]

Eco-pro goes off over a certain speed. I think it's 65mph. Have a look in the settings and it will tell you. I can adjust the threshold on mine up to the limit. As I tend to cruise faster than that on the motorway it's a waste of time for me.

The couple of times I did use it round town it saved 7 miles in a week. I've never used it since then as the blunted acceleration was a big downer.

[Andy_o]

Originally Posted by Ranger 6

Eco-pro goes off over a certain speed. I think it's 65mph. Have a look in the settings and it will tell you. I can adjust the threshold on mine up to the limit. As I tend to cruise faster than that on the motorway it's a waste of time for me.

The couple of times I did use it round town it saved 7 miles in a week. I've never used it since then as the blunted acceleration was a big downer.

Mine tells me to slow down at 75 mph if on Eco pro

[FSociety]

Originally Posted by Andy_o

Mine tells me to slow down at 75 mph if on Eco pro

I have my Eco-Pro set to maximum speed that allows me and its 80mph, so obviously I would save more if I had it set up at 60-70 lol.

Pictures of proof below 1/4 tank left 92mi earned and after that I was just driving at WOT until I hit 7 miles left range and 392mi on the tank.

90% highway, 10% standstill traffic, definitely a few WOT in Sport+ and shift the left while on Eco too to change lanes more aggressively.

[exilio]

THE ULTIMATE DRIVING MACHINE

Not the ultimate gas-saving, tree-hugging, Birkenstock-wearing, grandma-driving, machine...

Just sayin'! But impressive MPG!

[Rich4]

Originally Posted by ROBNYC

..... and after that I was just driving at WOT until I hit 7 miles left range......

Wow, that was brave

[buze]

Here's mine for the week-end; 4 people + kit onboard, MOST of the road was A road, and also quite lot of small mountain roads, with just a couple hours on the m-way (one way at 85mph, the other way at 70-mph on the cruise control to try to make a 'record' :-))

As you can see, there was still diesel in the tank! I personally think that a manual gearbox helps, also, the way you use the brakes...

[Peter_R]

It is a known fact that the newer 8 speed gearbox is more fuel efficient than any other previous system, be it manual or the earlier auto gearbox fitted to previous BMW series vehicles. After all that is the reason for its creation by ZF. The following link makes for good reading:

http://www.zf.com/corporate/en_de/pr...smission.shtml

This video says it all.....

http://www.zf.com/corporate/en_de/pr...smission.shtml

Also it is well documented that using the cruise control uses more fuel than without it because it uses the car's brakes to keep your speed within the predetermined user set range. Using the brakes unnecessarily increases the amount of fuel used.

If you want to get a complete overview of your fuel consumption, then an excellent tool for the job is the web site called fuelly http://www.fuelly.com/dashboard

After 3 years of driving several cars using the later ZF 8 speed auto gearbox I have found that there is very little gained by using ECO-PRO, so I now drive in Comfort mode all the time even at cruise on the motorway. I purchased the 3 litre diesel for its power and overtaking abilities not to drive like Grandma to say a few pennies on the fuel. I am still averaging 39.2 mpg over 8,500 miles.