07-06-2011, 06:25 PM
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#11 (permalink)
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Aero Deshi
Join Date: Jan 2010
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Quote:
Originally Posted by California98Civic
He recommends about 68mph on the highway (110kph). I suppose my civic would be up at about 3000rpm and would probably be in the vicinity of at least 70% load.
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Uh, how do you figure 70% load at 60mph? If you are not going uphill, you'd only be at 20-30% of the rated torque, thus load. Any more load and you'll be accelerating.
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Today
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07-06-2011, 07:09 PM
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#12 (permalink)
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Cyborg ECU
Join Date: Mar 2011
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Quote:
Originally Posted by ChazInMT
Uh, how do you figure 70% load at 60mph? If you are not going uphill, you'd only be at 20-30% of the rated torque, thus load. Any more load and you'll be accelerating.
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Correct. I'm accelerating. I was not clear. Accelerate in fifth, then decelerate in neutral, then repeat.
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See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.
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07-06-2011, 07:55 PM
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#13 (permalink)
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Master EcoModder
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Quote:
Originally Posted by kach22i
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That's definitely the sweet spot for me. I'm completely comfortable in the 75-100' range and you can hear and feel the difference in air flow over the car. You can watch the LOD drop and the MPG climb as soon as you crawl into the slipstream. I had a 77 mile stretch behind a semi once that averaged 48.8mpg at an average of 69mph. That included some bits over 80mph and some city-highway traffic around 60mph.
You don't have to get into the stupid-zone to get great mpg gains. All you need to do is enter into the disrupted airflow and low pressure zone and you make impressive gains.
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07-06-2011, 09:03 PM
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#14 (permalink)
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Aero Deshi
Join Date: Jan 2010
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Quote:
Originally Posted by California98Civic
Correct. I'm accelerating. I was not clear. Accelerate in fifth, then decelerate in neutral, then repeat.
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Glad yer not CraaaZzzzZy like the rest of us!
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07-06-2011, 11:14 PM
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#15 (permalink)
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Ultimate Fail
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Thank you very much for this article Piwoslaw. You always have good information to share with the group !
BTW, I find it amazing that the roof top luggage box was left on when he did one of his runs.
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07-08-2011, 05:12 PM
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#16 (permalink)
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The PRC.
Join Date: Oct 2009
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Quote:
Originally Posted by endurance
That's definitely the sweet spot for me. I'm completely comfortable in the 75-100' range and you can hear and feel the difference in air flow over the car. You can watch the LOD drop and the MPG climb as soon as you crawl into the slipstream. I had a 77 mile stretch behind a semi once that averaged 48.8mpg at an average of 69mph. That included some bits over 80mph and some city-highway traffic around 60mph.
You don't have to get into the stupid-zone to get great mpg gains. All you need to do is enter into the disrupted airflow and low pressure zone and you make impressive gains.
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Yep, I think slipstreaming is dumb because of the danger of emergency stops of debris from the vehicle in front's tyres. Keeping to the "2 second rule" (pick a point at the side of the road, count 2 seconds from when the vehicle in front passes it until you do. Less than 2 seconds you are too close) still means gains in my experience - the air vents go quiet and you can ease off the throttle with no loss of speed.
If someone fills the gap then that is usually because they are lane changing to exit or enter a motorway. My attitude is let them do this, it means you concentrate on them whilst they concentrate of getting to the outside lane asap and may not be watching you. And it means people can merge on/off without you braking.
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[I]So long and thanks for all the fish.[/I]
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02-12-2013, 03:34 AM
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#17 (permalink)
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ECOKINETIC DUDE
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One's for sure: doing 68 mph gets a much lower mpg than doing 55! Even Gerhard can't beat physics...
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02-12-2013, 05:02 AM
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#18 (permalink)
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Master EcoModder
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Thanks Piwoslaw,
I think that's the best paragraph is:
Quote:
Gerhard Plattner: "The best attitude is to consider fuel saving a kind of sport. Everybody who has enough money for a strong car, can drive fast and hit the pedal. But saving fuel requires concentration, self-control and cleverness. It's a challenge with the nice effect of saving you money that you can use for other more important things."
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I like it
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Quote:
Gerhard Plattner: "The best attitude is to consider fuel saving a kind of sport. Everybody who has enough money for a strong car, can drive fast and hit the pedal. But saving fuel requires concentration, self-control and cleverness. It's a challenge with the nice effect of saving you money that you can use for other more important things."
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02-12-2013, 11:13 AM
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#19 (permalink)
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ECOKINETIC DUDE
Join Date: May 2009
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constant travelling speed versus mileage
One's for sure: doing 68 mph gets a much lower mpg than doing 55! Even Gerhard can't beat physics...
Shooting for Guinness World Records one has basically to figure out at which speed a specific car gets the best mileage. With most cars that speed is somewhere between 60 and 90 km/h (37 - 56 mph). Now, european trucks generally travel at 89 km/h (ca. 55 mph, yes they usually exceed their 80 km/h speed limit by 10+ %). Hypermilers would have to travel that speed in order not to disturb traffic flow on the RH lane. Yes, it's a sport and a lot of concentration is needed to shoot for best mileage. It's a sportier way of driving than putting 'the pedal to the metal'.
As Gerhard is generally averaging 75 - 80 km/h on his record drives, his highway speed would be closer to 90 than 110 km/h. Each km/h above 90 will reduce mileage by ca. 1%
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02-12-2013, 01:42 PM
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#20 (permalink)
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The PRC.
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This is old.
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[I]So long and thanks for all the fish.[/I]
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