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  Reply # 2092282 18-Sep-2018 08:36
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kryptonjohn:

 

It's amazing how much difference a 1.6km change in elevation makes over a 331km drive. On the weekend the drive from Auckland to the top of the Bruce Rd at Mt Ruapehu I averaged 7.8l/100km. On the drive back home I averaged 6.5l/100km! Similar traffic conditions each way - perhaps less traffic driving down meant higher average speed and worse economy though. 

 

 

 

 

 

 

Interestingly my car uses less gas at 135 than 100. Drops down to around 7L per 100Km at 135 and 8.5L per 100KM at 100. I think it is due to the car covering more ground for fuel burnt and thats in the sweetspot for that chassis. 





 


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  Reply # 2092285 18-Sep-2018 08:41
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My car is a square box on wheels (Skoda Yeti).

 

At 80km/h it'll cruise along at 5.2L/100km.

 

At 100km/h it'll use 6.0L/100km.

 

At 120km/h it'll drink 6.8L/100km.


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  Reply # 2092295 18-Sep-2018 09:04
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Haven't done a scientific survey but I would say the Touareg is cheapest at a low speed say 80kph, level, straight line, constant speed about 4.6l/100km. That's barely into 8th gear.


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  Reply # 2092326 18-Sep-2018 09:29
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My Range Rover is better over long distances pottering around 90 - 100. It'll return around 13l/100

Push hard and you can get to 17l/100! More if you drive like Schumacher.





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  Reply # 2092336 18-Sep-2018 09:37
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I can get the Touareg to say no more than 40l/100kph with the foot to the floor towing a boat up a hill!

 

Either that's as much as the fuel pump and injectors can deliver or the computer gets too shy to tell the truth! Given that the speed could be anything but the number maxes out at 40 I guess it's the latter. It is a VW after all!   :-O

 

 

 

 


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  Reply # 2092357 18-Sep-2018 10:04
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I'll have to have another look at the Fuelly app. I did have it, but the current car does the average and instant consumption numbers.

 

Last time I looked, it was around 10-11L\100 km's as a result of a lot of around town driving. It should get into the high 6's on a the open road.

 

Car is Holden Cruze SRi-V Hatch with the 1.4iTi turbo'd motor with the Auto 'box.

 

On the subject of petrol, has anyone filled up at a Allied station? No problems with there 91?

 

I'm going up to Taupo at the beginning of the school holidays and don't want to pay Wellington prices for a fill up (2.349 BP Mana\Johnsonville or 2.389 at BP Wellington)




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  Reply # 2092372 18-Sep-2018 10:19
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WyleECoyoteNZ:

 

I'll have to have another look at the Fuelly app. I did have it, but the current car does the average and instant consumption numbers.

 

Last time I looked, it was around 10-11L\100 km's as a result of a lot of around town driving. It should get into the high 6's on a the open road.

 

Car is Holden Cruze SRi-V Hatch with the 1.4iTi turbo'd motor with the Auto 'box.

 

On the subject of petrol, has anyone filled up at a Allied station? No problems with there 91?

 

I'm going up to Taupo at the beginning of the school holidays and don't want to pay Wellington prices for a fill up (2.349 BP Mana\Johnsonville or 2.389 at BP Wellington)

 

 

 

 

Lol BP Clifton had 98 for 2.7xx something the other day. 

 

 





 


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  Reply # 2092382 18-Sep-2018 10:30
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Coil:

 

kryptonjohn:

 

It's amazing how much difference a 1.6km change in elevation makes over a 331km drive. On the weekend the drive from Auckland to the top of the Bruce Rd at Mt Ruapehu I averaged 7.8l/100km. On the drive back home I averaged 6.5l/100km! Similar traffic conditions each way - perhaps less traffic driving down meant higher average speed and worse economy though. 

 

 

 

 

 

 

Interestingly my car uses less gas at 135 than 100. Drops down to around 7L per 100Km at 135 and 8.5L per 100KM at 100. I think it is due to the car covering more ground for fuel burnt and thats in the sweetspot for that chassis. 

 

 

 

 

Umm - i guess it could appear this way from a cursory review of speed, mileage and fuel use from your gauges.

 

But measured properly - and even though my physics is pretty ropey nowadays - i don't think what you are claiming is physically possible - ie. from an energy perspective / 1st law if thermodynamics.

 

What with kinetic energy being a product of v2 - this greater speed requires more input energy output from your engine = more fuel needed....

 

 

 

 

 

 

 

 




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  Reply # 2092383 18-Sep-2018 10:30
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kryptonjohn:

 

I can get the Touareg to say no more than 40l/100kph with the foot to the floor towing a boat up a hill!

 

Either that's as much as the fuel pump and injectors can deliver or the computer gets too shy to tell the truth! Given that the speed could be anything but the number maxes out at 40 I guess it's the latter. It is a VW after all!   :-O

 

 

 

 

 

 

 

 

If it is a V8 diesel then you will empty your fuel tank before you even do 50KM if it is 100% loaded in perfect conditions. (Like on a dyno)





 


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  Reply # 2092389 18-Sep-2018 10:44
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It's a V6 but everything from the V6 up to the V8 seems linear (number of cylinders, cubic capacity, rated power) so expect consumption would be the same...

 

Mate has a V8 Cayenne diesel. The VW V8 is 250KW but the different ECU maps in the otherwise identical Cayenne V8 give 300KW. Bastards.

 

 

 

 




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  Reply # 2092391 18-Sep-2018 10:47
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kryptonjohn:

 

It's a V6 but everything from the V6 up to the V8 seems linear (number of cylinders, cubic capacity, rated power) so expect consumption would be the same...

 

Mate has a V8 Cayenne diesel. The VW V8 is 250KW but the different ECU maps in the otherwise identical Cayenne V8 give 300KW. Bastards.

 

 

 

 

 

 

 

 

Trust me that V8 diesel has larger injectors and more of them. It DRINKS when you gun it. 
Just because it seems linear doesn't mean it is :) 
The maps can be changed but AFAIK the porsche does have a larger turbo, injectors and intercoolers.






 


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  Reply # 2092416 18-Sep-2018 11:20
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Oh hey more Fuelly users! I've been tracking all my cars since about 2012. I use L/100k as that's what's displayed on the dash of my car.

 

Out of interest I just exported all my fuel ups from 2012-current and chucked them into Excel, giving me a total of 47,377 KM logged, with 5,503L used and a total cost of $12,007.80 spent on gas. Average fuel cost was $2.18, min $1.799 and max $2.499 (sadly, my most recent).

 

My current ride:

 

 

And some previous cars (you may spot a purchasing pattern here). I think all but the first Golf are on 95/98 fuel.

 

My first car - 1.4L Golf

 

 

2.0T A4 Quattro

 

2.0T Golf GTI

 

2.0T A4 Quattro





 




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  Reply # 2092474 18-Sep-2018 12:55
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driller2000:

 

Coil:

 

kryptonjohn:

 

It's amazing how much difference a 1.6km change in elevation makes over a 331km drive. On the weekend the drive from Auckland to the top of the Bruce Rd at Mt Ruapehu I averaged 7.8l/100km. On the drive back home I averaged 6.5l/100km! Similar traffic conditions each way - perhaps less traffic driving down meant higher average speed and worse economy though. 

 

 

 

 

 

 

Interestingly my car uses less gas at 135 than 100. Drops down to around 7L per 100Km at 135 and 8.5L per 100KM at 100. I think it is due to the car covering more ground for fuel burnt and thats in the sweetspot for that chassis. 

 

 

 

 

Umm - i guess it could appear this way from a cursory review of speed, mileage and fuel use from your gauges.

 

But measured properly - and even though my physics is pretty ropey nowadays - i don't think what you are claiming is physically possible - ie. from an energy perspective / 1st law if thermodynamics.

 

What with kinetic energy being a product of v2 - this greater speed requires more input energy output from your engine = more fuel needed....

 

 

 

 

 

 

 

 

 

 

 

 

I think at the same time you need to consider the new velocity and the new rate of ground covered also gear ratios and RPM. My gearbox throws my car into 5th around 90KPH then overdrive in 5th around 110 and that makes a noticeable difference.

I rely on my economy gauge on the dash so it could be wrong... 






 


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  Reply # 2092483 18-Sep-2018 13:19
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If you think cars are expensive to fuel ... get a boat. 

 

Pushing into a lippy southerly on a recent  homeward trip I was using 1.5L per km at one point.





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  Reply # 2092488 18-Sep-2018 13:23
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Coil:

 

driller2000:

 

Coil:

 

kryptonjohn:

 

It's amazing how much difference a 1.6km change in elevation makes over a 331km drive. On the weekend the drive from Auckland to the top of the Bruce Rd at Mt Ruapehu I averaged 7.8l/100km. On the drive back home I averaged 6.5l/100km! Similar traffic conditions each way - perhaps less traffic driving down meant higher average speed and worse economy though. 

 

 

 

 

 

 

Interestingly my car uses less gas at 135 than 100. Drops down to around 7L per 100Km at 135 and 8.5L per 100KM at 100. I think it is due to the car covering more ground for fuel burnt and thats in the sweetspot for that chassis. 

 

 

 

 

Umm - i guess it could appear this way from a cursory review of speed, mileage and fuel use from your gauges.

 

But measured properly - and even though my physics is pretty ropey nowadays - i don't think what you are claiming is physically possible - ie. from an energy perspective / 1st law if thermodynamics.

 

What with kinetic energy being a product of v2 - this greater speed requires more input energy output from your engine = more fuel needed....

 

 

 

 

 

 

 

 

 

 

 

 

I think at the same time you need to consider the new velocity and the new rate of ground covered also gear ratios and RPM. My gearbox throws my car into 5th around 90KPH then overdrive in 5th around 110 and that makes a noticeable difference.

I rely on my economy gauge on the dash so it could be wrong... 


 

 

 

 

sorry, but nope - none of what you said changes a fundamental law of physics.

 

 

 

ps: gearing will change engine rpm for a given velocity - but its throttle position that determines fuel use - and to go faster you will still need to burn more fuel

 

And - drag is also based on v2 as well - so your doubly borked the faster you go.


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