[boonkgang13k]

Surprisingly Sport Mode more efficient on highway for 530e... I guess that's because it holds up high speeds better?

[hlothery]

Don't know much about the 530e. I can tell you, however, that if you believe the eco guage you can call up on the on board computer, mileage drops significantly in the M550i when you go from Comfort mode to Sport or Sport Plus.....even in cruise control on the highway. Makes sense.....RPMs increase due to different gearing chosen in the Sport map for the ZF8 transmission; fuel maps change in the engine; turbo waste gates close, so the turbo's spin up; exhaust valves open, etc. Don't get me wrong......I love Sport Plus! But gas mileage considerations go out the window in the M550i when you select that mode, and I have no problem with that. YMMV.

[cartaozinho]

Originally Posted by hlothery

Don't know much about the 530e. I can tell you, however, that if you believe the eco guage you can call up on the on board computer, mileage drops significantly in the M550i when you go from Comfort mode to Sport or Sport Plus.....even in cruise control on the highway. Makes sense.....RPMs increase due to different gearing chosen in the Sport map for the ZF8 transmission; fuel maps change in the engine; turbo waste gates close, so the turbo's spin up; exhaust valves open, etc. Don't get me wrong......I love Sport Plus! But gas mileage considerations go out the window in the M550i when you select that mode, and I have no problem with that. YMMV.

Yeah, 'cause we bought V8 sedans with fuel consumption forefront in our minds!

In the same vein -- I was talking with a colleague the other day about electric vehicles (EVs) and road wear and tear. Traditionally, fuel efficiency was a good approximation for how much wear and tear a car puts on the road (weight miles is the "best" metric but since heavier cars tend to be less fuel efficient, gasoline consumption is a good approximation that doesn't need detailed accounting). In such a world, excise taxes on gasoline are a good approximation for the amount of wear and tear each car puts on the road. With the advent of electric vehicles (EVs) this isn't true any more -- EVs tend to run heavy (for their size). And pure EVs like Teslas pay zero in gas taxes. That is, EVs are tearing up the roads but not paying a dime to help repair them (this is changing in CA and IL). I then mentioned that buying a V8 sedan was, in my consideration, a huge public service -- terrible gas mileage (i.e. paying lots of gas taxes) without too much wear and tear on the roads! Not like those selfish Tesla owners!

[HighlandPete]

Originally Posted by boonkgang13k

Surprisingly Sport Mode more efficient on highway for 530e... I guess that's because it holds up high speeds better?

Is that from brimmed tests, or simply OBC readouts?

Most unusual for higher revs to be more fuel efficient in something like a sedan. Maybe there is some anomaly in the 'e' drivetrain function that changes the 'road load', but typically (in a gasoline engine) more revs increase the total/frictional losses.

[SteveinArizona]

seems hard to believe, especially since sport mode prevents the car from going into 8th gear.