Blue_boost
Kennel Enthusiast
- Joined
- May 19, 2014
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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.
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.