Just had a bit of a laugh, thought i might share.

TuMor · 02-02-2008, 08:03 PM

Just heard a corker from one of my little brothers mates, drives an oldish 5.0 statto.
Talking about economy driving he's adamate that the power button gives him heaps better economy...also says he saves heaps of petrol driving fast up to the speed limit so he can put the cruise control on sooner.

This from a kid who argued with my brother that Hitler killed 60million Jews in WW2.

**TUF_302** · 02-02-2008, 08:07 PM

Oh dear!!!

:

andrewts · 02-02-2008, 08:08 PM

Hrm, I noted slightly better economy in Power when navigating the hills in the Northern Beaches area of Skidney than in Economy, as the engine labours more at lower RPM in Economy than in Power, and it uses more fuel than if it just spins a bit faster labouring less. If that makes sense. As for racing up to speed and then putting cruise on, I highly doubt that would save fuel. :P

**aussiblue** · 02-02-2008, 09:14 PM

There is a lot of research including some done by Mercedes Benz published in Road and Track some years ago that shows on a trip brisk acceleration to the desired cruising speed, while giving a momentary heavy fuel consumption, will give a better overall trip economy i.e. using more fuel for a shorter period can be more fuel efficient than accelerating slowly and having less than optimal fuel consumption for a longer period.

AuFairlaneV8 · 02-02-2008, 09:20 PM

Quote:

Originally Posted by aussiblue

There is a lot of research including some done by Mercedes Benz published in Road and Track some years ago that shows on a trip brisk acceleration to the desired cruising speed, while giving a momentary heavy fuel consumption, will give a better overall trip economy i.e. using more fuel for a shorter period can be more fuel efficient than accelerating slowly and having less than optimal fuel consumption for a longer period.

Yeah I heard something similar, some researcher came to the conclusion that using 75% of the cars acceleration potential to get up to the speed limit is optimum for saving fuel.

pauljh74 · 02-02-2008, 09:23 PM

Quote:

Originally Posted by TuMor

Just heard a corker from one of my little brothers mates, drives an oldish 5.0 statto.
Talking about economy driving he's adamate that the power button gives him heaps better economy...also says he saves heaps of petrol driving fast up to the speed limit so he can put the cruise control on sooner.

This from a kid who argued with my brother that Hitler killed 60million Jews in WW2.

Moderate acceleration up to your desired speed can give better economy than very light throttle as it enables the car to hit a higher gear sooner, which is better for economy. But if he is going hard it'll drink more.

**aussiblue** · 02-02-2008, 09:26 PM

Some more recent similar research(albeit with diesel trucks) that was based on MB earlier car research. I am still seeing if I can find that earlier MB paper.

http://inderscience.metapress.com/me...q8lvj9gxkl.pdf

Quote:

The optimal acceleration – torque relation defines a driver’s attitude towards vehicle
acceleration. It refers to the proper application of torque in order to accomplish a
given road distance, without needing to set the acceleration pedal to its full position,
which is not recommended during gear shifting. The gear shifting needed depends on
the road conditions.
The conservation of momentum principle takes advantage of the vehicle’s inertia.
When used by the driver, it will keep the vehicle as much as possible at constant
speed, thereby saving fuel. For a correct observation of this principle, the driver has
to forecast some traffic situations, especially in suburban areas. The cruise speed is
reached more rapidly during a given operation.

bodes-sh · 02-02-2008, 09:36 PM

yeah, well it's all very well getting there quickly, but the amount of people that can't stay there and keep speeding up and slowing down doesn't help fuel consumption

**aussiblue** · 02-02-2008, 10:47 PM

I guess the real point is that the often cited claim that you get the best fuel economy by driving like there is an egg under the accelerator peddle has been proven wrong numerous times (as well as such diving habits being perhaps dangerous in terms of frustrating other road users). "Brisk" rather than flat out acceleration giving early gear upshifts is the go.

andrewts · 02-02-2008, 11:27 PM

I know I'm keeping on about the Power/Economy thing, but when combine with brisker acceleration, which would be better?

I can't help but think that in the city there is no point in gunning it either.

**aussiblue** · 02-02-2008, 11:40 PM

Economy gives earlier shifts so is more economical. The power switch is all about later shifts and therefore usually poorer economy (except when towing or climbing mountains). So it will depend on your terrain and what you are pulling or carrying. Of course if you are racing for pink slips economy will cost.

andrewts · 02-02-2008, 11:45 PM

OK then, so I'll get into it a bit more on the next tank and see how we go. Currently sitting on about 420Km, with the guage just below half (I love fuel guages and the false hope they provide haha.)

Trevor 57 · 03-02-2008, 04:10 AM

Quote:

Originally Posted by TuMor

Just heard a corker from one of my little brothers mates, drives an oldish 5.0 statto.
Talking about economy driving he's adamate that the power button gives him heaps better economy...also says he saves heaps of petrol driving fast up to the speed limit so he can put the cruise control on sooner.

This from a kid who argued with my brother that Hitler killed 60million Jews in WW2.

Ford actually believed this for a while too with the EL's, if you push the cuise on early with those, they would drop back a gear and go like crazy to your pre-set speed.

And I fail how all this relates to WWII, but I guess I must be missing something, unless the early Volkswagens did it too -

**aussiblue** · 03-02-2008, 12:09 PM

6 million is sort of close to 60 million.

Rodp · 03-02-2008, 08:11 PM

I know my EF had better economy in power in heavy traffic as it didn't want to change up a gear in stop start traffic. I believe this was also recommended by Ford at the time.

I'd also heard about studies in accelerating briskly to the speed limit and then hitting cruise to be more economical.

Ok, his numbers are a little off with regards to the Jews but you can't always be right...

paul_r_d · 04-02-2008, 01:22 AM

ok.... dumb question, my VX had a power button.... i had no idea what it was for, and never used it.....what they hell do they do....

Trevor 57 · 04-02-2008, 11:27 AM

The power button ii the Falcons is fantastic when towing or driving in hills.

It holds the gear longer before changing up or down.

In power, when towing or in hills the engine will only drop a few revs before the transmission changes down, whereas in normal, the revs will drop a fair bit before changing down. It enables the car to maintain better speed.

You wouldn't notice much difference when driving around on flatish ground.