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Ross
05-13-2008, 07:26 AM
Prompted by my first >$4/gl. fill-up.
On a 140 mile journey using country roads, short shifting, not exceeding 75mph.
This is OBC indicated, I will confirm but am none the less impressed. The 'ol M30 couldn't do this if dropped from a cliff.

healtoeit
05-13-2008, 07:27 AM
Prompted by my first >$4/gl. fill-up.
On a 140 mile journey using country roads, short shifting, not exceeding 75mph.
This is OBC indicated, I will confirm but am none the less impressed. The 'ol M30 couldn't do this if dropped from a cliff.
yea sure... but how much fun was it short shifting through country roads?

Ross
05-13-2008, 07:35 AM
This was an experiment.
Seeing about a 25% improvement in fuel economy simply by changing driving style may have me experimenting more often though.
Next weekend will have me traveling around twice the distance on interstate highways. I'm curious to see what she'll do.

healtoeit
05-13-2008, 07:55 AM
This was an experiment.
Seeing about a 25% improvement in fuel economy simply by changing driving style may have me experimenting more often though.
Next weekend will have me traveling around twice the distance on interstate highways. I'm curious to see what she'll do.
I was just being a dick. I do the same experiments to try and stretch my gas tank, but when i'm "experimenting" I never...ever.... have a smile on my face.
:D

ryan roopnarine
05-13-2008, 10:58 AM
a few years ago, a 530 owner indicated that they could get 34-35mpg when they went 55-60 continuously. that jives with my maximum 36mpg that i got over 100 miles once in my 525i. i don't know if the extra litre of displacement would make that un-doable in your car, but you could try. for other data in my 525i==

maximum of 30mpg at 70 over 100 miles on fresh 5w30, ac on 100%
28mpg at 75 over same distance and oil with less than 500 miles on it.
30 mpg at a effective average speed of 72 mph (actual speed was around 85mph) over 19 hours and 1400 miles--2 passengers and trunk full of crap. i don't speed anymore, so it should be higher.

Mr._Graybeard
05-13-2008, 11:06 AM
I use my 540i on a 40-mile freeway commute, and my OBC also registers 23.3 over many tanks (a couple months' worth at least). I think that reading is actually a little pessimistic.

While I don't regularly redline the motor, the car does see 4500-5000 rpm on freeway ramps, stretches at 80 mph and occasional spurts at higher speeds (like getting around uncovered gravel trucks).

The car has a Dinan chip and I burn premium. That seems to have boosted highway economy slightly from the stock fuel map. Figuring in the extra cost at the pump, it's probably a wash.

pgrindstaff
05-13-2008, 11:08 AM
When I was driving my car back from PA my dad and I managed to up to 28mpg going through mountains. Much like you, I was quite impressed. On my commute to work in the mornings I get between 19 and 23 mpg. Trying to get home kills it though :(

e34.535i.sport
05-13-2008, 11:33 AM
The 'ol M30 couldn't do this if dropped from a cliff.

I got 25.4mpg on a run last night after conducting the compression test (wanted to try and give the battery back some charge!)...

It was over about a 65+mile trip with about 70%highway 25%city and 5%Burger King Drive through. OBC indicated of course but it's normally within 0.5mpg give or take so I was impressed!

This is with Shell V-power in conjuction with the EAT chip...

bimmerd00d
05-13-2008, 01:49 PM
I did this this past weekend in my E39 540. I went from my usual 24mpg to nearly 29. My normal avg speed was about 74mph, changed it to about 68 and the mileage shot through the roof.

Ross
05-13-2008, 03:19 PM
Well, I topped up first thing this morning to verify the OBC, the math said 23.0 mpg but I may have filled the tank a bit more too so the OBC looks to be almost dead on.
Sadly, today's slog through traffic and less conservative driving style has the average back down to 21 something already and falling. I need to adjust my driving style a bit, and remember there is that 6th gear ratio.

scott540
05-13-2008, 03:49 PM
I'm always amazed that I get about 15 in town and on the highway 75-80mph in 6th gear I can get 26-28. Think about 10 more miles per gallon over a tank of gas adds up to a lot

Robin-535im
05-13-2008, 06:45 PM
...The 'ol M30 couldn't do this if dropped from a cliff.
I'll get 23-24 in my M30 if I drive really easy and only goose it a few times a day - which is hard to do.

A few months ago I was trying to get the best mileage possible, so I never gave it more than 1/8th pedal, shifted before 2000 RPM, took it real easy and really slow. I recall pulling away at a stop light and noticing that all the cars around me were going really slow too, and I thought, "Hmmm... they must all be trying to get good mileage too!" - then I realized that that was just the normal speed that normal people drive. ;)

RX7guy
05-14-2008, 10:40 AM
I'm always amazed that I get about 15 in town and on the highway 75-80mph in 6th gear I can get 26-28. Think about 10 more miles per gallon over a tank of gas adds up to a lot

That 6th gear is great isn't it? :D

Elekta
05-14-2008, 10:49 AM
That 6th gear is great isn't it? :D
yes it is, especially the 4th to 6th shift.

air up your tires to 45psi and get another 3% mileage improvement on the hwy

bobchiba
05-15-2008, 10:53 AM
I have the 6cyl 530i, im in the uk, and if I stick to 70mph on a motorway run, i usually get 36-39mpg, and 30mpg when i hover around 80-90mph.

stx133
05-16-2008, 02:04 AM
Have run as good as 27.6 on HWY only regular s 23.5