Car fuel economy rationalisation thread

Blue_boost

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When I read a new cars fuel economy claims, is it really comparable on the methods of testing from car to car ?

For instance if some econocar states it can achieve 5.5L/100km fuel economy, you look at it's motor and it's probably got 60kw of power ... So I ask would it achieve those fuel economy numbers if you have to keep up with traffic? Probably having to really stretch its legs to hit 6000rpm in every gear to keep up. Would it still achieve that fuel economy in that scenario ?

Then on the other spectrum , a big V8 that might state it can do 14L/100km but that is likely achieved easily keeping with traffic. Just tooting along at 2000rpm.

So if we established a real "keep up with the traffic" metric, whereas cars would be tested accelerating at a pace of say 10 seconds from 0-100km/h, the econocar would be launching hard and redoing every gear just to achieve that pace whereas the big V8 is just cruising along to hit that pace.

The real fuel economy would be much closer real world?

Don't get fooled by econocar fuel economy claims, it's likely tested at a snails pace at low rpm, unlivable day to day in real traffic huddle.

Years back I drove a Hyundai gets to QLD and back from Sydney. Geez it used some fuel as it required a high average speed 110-115km/h and the revs were up the whole way.

Whereas I've done the trip in a big 6 and V8 and it's barely at 2000rpm at the same speed, the fuel used was actually very similar over the entire trip? But the Hyundai's advertised fuel economy would have been half the big car. It just wasnt so in real life conditions.

We should establish a keep pace with traffic metric, then all cars need to be tested under those conditions, a few hills in there as well and let's see how the fuel economy goes.
 

Memberberries

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No one believes me that I once squeezed over 1000km out of a VY.

I made 3 trips to Katoomba and back in a week to clock that up.
The trick is when coming back to Sydney,is not to accelerate so frequently.

Coming back to Sydney from the blue mountains is mainly a downhill run back!
So you’d have to be dumb to use your accelerator and waste fuel when you can just let the mountains coast you home most of the way!
 

KambahOne

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No one believes me that I once squeezed over 1000km out of a VY.

I made 3 trips to Katoomba and back in a week to clock that up.
The trick is when coming back to Sydney,is not to accelerate so frequently.

Coming back to Sydney from the blue mountains is mainly a downhill run back!
So you’d have to be dumb to use your accelerator and waste fuel when you can just let the mountains coast you home most of the way!
Arh good ole "angel gear" to use a truck driving parlance.

Eco ratings on anything is a bit of a con. For instance they'll rate a car based on the 'average' number of this and the 'medium' number of that as they don't do any real testing. It's an algorithm derived from the size of the engine, wheel size, gear ratio etc. They come up with a number, divide it by the number of letters in the name of the car and promote it as environmentally friendly. Even the "eco" buttons you have in your modern cars simply reduce the effectiveness of your accelerator by 50% so you think you're driving economically.
 

Memberberries

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Arh good ole "angel gear" to use a truck driving parlance.

Eco ratings on anything is a bit of a con. For instance they'll rate a car based on the 'average' number of this and the 'medium' number of that as they don't do any real testing. It's an algorithm derived from the size of the engine, wheel size, gear ratio etc. They come up with a number, divide it by the number of letters in the name of the car and promote it as environmentally friendly. Even the "eco" buttons you have in your modern cars simply reduce the effectiveness of your accelerator by 50% so you think you're driving economically.
I must be an alright driver?
Most truck drivers sit behind me in heavy traffic because I don’t speed up and keep hitting my brakes!
Honestly Sydney motorists, why are you in such a fucking hurry? Lol

You aren’t going anywhere in peak hour!
Just take a chill pill and get used to the fact 40km is top speed on the freeway but average speeds are 25km.

What do Sydney motorists have against leaving a 30 metre safe gap between vehicles in heavy traffic?
It’s smart to keep your distance in heavy traffic!
 

Raysie

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Another thing I'd be interested to know. Would having a larger size tank mean less fuel is consumed compared to a small tank that would burn through fuel faster?
 

belmore_utd

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My 3 most recent cars

Sonata 2006 XF v6 3.3 litre - fuel economy 10.5L/100km

Mazda 2012 CX7 2.5 litre 4 cyl - fuel economy 9L/100km

Nissan 2016 Quashqai TL 1.6 cyl turbo Diesel - fuel economy 7.8L/100km

In my experience I live in a rural area and the best economy is driving between towns at a consistent 100km without much stopping and starting. Bigger engines excel here.

Smaller engines give better economy when you are in a city or town and driving in traffic with constant stops and starts.

Simples.

Btw if you are really jamming 6000 rpm's into a car to change gears calm the fuck down Lowndesy.

In all the above cars and many others I have driven in between, gear changes are optimal from 2300 to 3500 rpm and if you can't hum along a highway at 1800-2300 rpms at 100-110km than get your car checked.

Edit - Just double checked the qashqais supposed fuel economy is 4.9L/100km hahaha. Maybe under zero gravity conditions. No way is that achievable. I am not a lead footed driver by any means (these days)
 
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KambahOne

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I must be an alright driver?
Most truck drivers sit behind me in heavy traffic because I don’t speed up and keep hitting my brakes!
Honestly Sydney motorists, why are you in such a fucking hurry? Lol

You aren’t going anywhere in peak hour!
Just take a chill pill and get used to the fact 40km is top speed on the freeway but average speeds are 25km.

What do Sydney motorists have against leaving a 30 metre safe gap between vehicles in heavy traffic?
It’s smart to keep your distance in heavy traffic!
We only have peak half hour in Canberra but trust me, Canberra drivers can squeeze an hours worth of stupid into half an hour.
 

CroydonDog

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Diesel FTW.

Volvo XC60. a 2 tonne car. getting down to a bit over 6lts/100 km city / about 9 in the city.
 

Motorhead

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No one believes me that I once squeezed over 1000km out of a VY.

I made 3 trips to Katoomba and back in a week to clock that up.
The trick is when coming back to Sydney,is not to accelerate so frequently.

Coming back to Sydney from the blue mountains is mainly a downhill run back!
So you’d have to be dumb to use your accelerator and waste fuel when you can just let the mountains coast you home most of the way!
Wouldnt the fuel economy be evened out by having to drive up those same mountains in the first place though?
 

coach

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No one believes me that I once squeezed over 1000km out of a VY.

I made 3 trips to Katoomba and back in a week to clock that up.
The trick is when coming back to Sydney,is not to accelerate so frequently.

Coming back to Sydney from the blue mountains is mainly a downhill run back!
So you’d have to be dumb to use your accelerator and waste fuel when you can just let the mountains coast you home most of the way!
Thing about going downhill is you also have to go up it.... and more fuel usage...
Where else did you drive for the 1000km’s
Sydney to Katoomba you might punch out 600k in 3 trips
7l/100 and that’s if you ran it dry, so more like 6 odd litres per 100km in a vy commodore driving up the blue mountains 3 times....
Few holes here....
 
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Blue_boost

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Thing about going downhill is you also have to go up it.... and more fuel usage...
Where else did you drive for the 1000km’s
Sydney to Katoomba you might punch out 600k in 3 trips
7l/100 and that’s if you ran it dry, so more like 6 odd litres per 100km in a vy commodore driving up the blue mountains 3 times....
Few holes here....
I'm a belieber.

Half the km are uphill and half are downhill.

If on cruise control on the way up it's possible to achieve 10l/100km if doing maybe 85km/h

On the way down your going at say 115km/h downhill doing maybe 5l/100km.

So between the two runs you see around 7.5l average per 100km.

With a 68 litre tank at 7.5L/100 there is 906km in the bag.. give it 5-6 litres of emergency fuel level and you are real close to 1000km.

Be a guy that's half full instead of empty. Plus memberberries don't strike me as a bullshitter ...

Be a belieber
 

086

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Trick for decent fuel economy, is to drive a car like a road train, or a control it like an actual train with metal on metal braking/acceleration.
Currently getting 6-7l/100km w/ a 2015 corolla and managed a litre less in the courtesy Kia Cerato I had for a week, and that's city driving!
 

coach

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I'm a belieber.

Half the km are uphill and half are downhill.

If on cruise control on the way up it's possible to achieve 10l/100km if doing maybe 85km/h

On the way down your going at say 115km/h downhill doing maybe 5l/100km.

So between the two runs you see around 7.5l average per 100km.

With a 68 litre tank at 7.5L/100 there is 906km in the bag.. give it 5-6 litres of emergency fuel level and you are real close to 1000km.

Be a guy that's half full instead of empty. Plus memberberries don't strike me as a bullshitter ...

Be a belieber
Katoomba to Penrith is 50km, so bout 45 is downhill
That’s 135km out of the 1000 downhill......

Looks even more dubious
I’d say not bullshitting more memory and what actually ddI happen
Once you start crunching numbers it seem very very unlikely
Just saying from a mathematic perspective
 
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Memberberries

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Thing about going downhill is you also have to go up it.... and more fuel usage...
Where else did you drive for the 1000km’s
Sydney to Katoomba you might punch out 600k in 3 trips
7l/100 and that’s if you ran it dry, so more like 6 odd litres per 100km in a vy commodore driving up the blue mountains 3 times....
Few holes here....
I drove around the Sydney basin also. About 400km of driving on flat land and 600 for the mountain trips
So yeah just a touch over 1000km running a full tank down to empty!

Don't give a shit if you heavy lead footed automatic drivers dont believe me.
I know what I achieved!
 

Memberberries

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Lately I’ve only been lucky to get 500km out of a Camry.

Reason being is I lose my cool on the road when a young female P player who always wants to send texts at every red light try’s speeding up to over take me!

Yeah right!
I don’t want a shit female driver who is easily distracted by her phone to get in front of me and slow me down! Haha
 

086

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She just wants some rear end action from you ;)
 

Memberberries

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She just wants some rear end action from you ;)
Watch on the roads when stuck at a set of lights.

Nearly every young p plater who is female of the species all think they’ve mastered waiting at lights while sending text messages!


I shouldn’t of listened to my uncle, I knew I should of cleaned myself up and became a cop.
I’d just be fining P platers for using their mobile phones all day!
 

086

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Not worth the stress and in particular, the grooming done at Goulburn in order to 'think' how they want you to!
You're a free mind, relatively speaking, compared to poor pigs, who aren't!
That's the reason why they tend to flock together post work, as their approach to life clashes with the rest of us!

There's a few cops/ex cops here.
You can tell based upon their posting style alone.
One was honest enough to admit to it at least.
Don't respect the majority of what he posts, yet give him credit for at least being honest about that!
 
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