Who says racing has nothing to do with fuel economy? Honestly, I was rather shocked to hear about the prominence of hypermiling techniques in racing, especially NASCAR. Perhaps the revolution is hitting home with more people than the news would lead us to believe. Here’s the word direct from Earnhardt and ESPN:
Knowing the race was going to be extended beyond its scheduled 200 laps, Eury told Earnhardt to shut the engine off and coast whenever he could under the caution flag in a desperate effort to save more gas.
Junior did just that, coasting fast enough at times that he passed the pace car — until NASCAR warned Eury to have Earnhardt cut it out.
“I didn’t know how much they were going to worry about it,” Earnhardt said. “All the cars out there are gassing it, shutting ’em off, coasting about a half straightaway, cranking ’em back up, gas it, coast. Everybody’s doing it.
For those of you who don’t know already, this technique is oftentimes called “Pulse & Glide,” and is widely used by ecodrivers looking to get better gas mileage. P&G works by making your engine work only when it’s most efficient, and shutting it off at other times.
P&G, as the name suggests, has two main components. The pulse is an acceleration phase with lots of throttle, and the glide is a coast in neutral or with the engine off. People using P&G for fuel economy will often pick a median speed and pulse up to 10 MPH above that and then glide down to 10 MPH below, so that they can maintain an average speed around where the would be driving anyway.
It works because your engine is most efficient in high load operation, and then uses no fuel if you’re coasting with the engine off, as Earnhardt did. Rather than being in a constant low load, inefficient state, the combination of burning more during acceleration and then none during coast averages out to savings. While it may seem counter intuitive, Earnhardt’s victory clearly shows that it’s a viable technique.
Now, that said, I do not recommend using P&G in traffic where other drivers might not know what you’re doing or it might be dangerous. It’s best at low speeds (where aerodynamics is not so much of a factor) and when you have an open road that you know well. For a better description of P&G, see this MetroMPG.com article. For more fuel efficient driving techniques check out the 100+ EcoDriving Tips list.
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If you are going to cash off of Dale Jr’s popularity by plugging his name in his article, maybe you should have the decency to include a picture of the car he drives.
Unless you own an image you would let us use, it would be illegal to just go and find one and throw it up.
So perhaps your question of “decency” should be about stealing intellectual property by using pictures of his car that we don’t own, :p
touche Benjamin Jones, touche.
The fact that you mention to only try on roads you know well with low traffic is scary. I understand trying to save some money and the ‘world’, but geez… worry about OTHER peoples safety first. Go hug a tree or something you hippie.
Wait, Benjamin Jones, do you own the international property to the photo that you put up there? Furthermore I am sure a young and budding photographer would love to have their picture featured here. I think it is a little ridiculous to have a picture of nascar racer when talking about another.
Here, I can help.
Go here:
http://www.flickr.com/photos/tags/daleearnhardtjr/
Find one that’s saved under creative commons license. Or a free license. (You’ll see the little CC logo in the information) and be sure to leave a credit/link for the photographer.
Oh, I almost forgot my main comment:
Racecar drivers have been using “hypermile” techniques for decades to win races. It might be interesting to pick the brains of some of the better ones at winning fuel mileage races to get ideas for the road.
Yeah, lots of luck with that. The picture of the Petty car may or may not be a violation of NASCAR rules, STP’s copyright, blah blah blah and it’s getting to where you can just barely mention NASCAR without cutting a check. So…my guess is that a generic track photo is all that will be allowed in the future. 🙁
so what, instead you put up a picture you don’t own of someone else’s car?
Doing an advanced search on Flickr requesting results with a specific Creative Commons License allowing you to use the image is easy enough and such images are rather abundant.
See: Flickr.com > Search > Advanced Search > Only search within Creative Commons-licensed content
I then restricted the results to any date taken after February 2008 as to get Juniors new car/sponsor/number.
I’ve done this down long grades when i’m running very low, just remember to keep the key in the ON position else deal with steering wheel locking on you. It should also be said that in most cases you lose power everywhere, including steering and brakes.
Anon: The advise isn’t meant to scare you, it’s meant to keep you from being inconvenient to others. Just like driving 35 MPH on the highway isn’t good, P&G in traffic isn’t good.
To everyone commenting on the image: I did use the flickr CC search, but wasn’t looking for the right thing, I was kinda sleepy when I put the picture up, no one is perfect, :p
Changing it now.
power steering and braking may not work with the engine off… best of luck
Too all you you saying why would you put a picture of another driver up when you are talking about Dale Jr. shows how very little all of you know about NASCAR. That is Dale Jr.’s car. It is NOT his current car. He drove the number 8 car last year.
Still the wrong car. Budweiser was last year.
http://www.dalejr.com/#myride
Umm… Dale’s number is 88 now, not 8. He quit driving for DEI at the end of last year. He now drives for Hendrick Motorsports and is sponsored by Amp and the National Guard.
Still not his car.
I have no idea how this coasting is supposed to work.
In a car the brake cylinders are powered by the engine. If you shut the engine off you have the pressure in the system (one or two presses on the brake) after this the brakes on the car will not work.
And I completely forgot to add, what about the steering? Switch the engine off and you lose power steering.
In a car built with power steering, turning it off means you have to apply 5x the force on the wheel to change direction.
Imagine having to dodge something on the road quickly, not only do your brakes not work, but neither can you steer (at all) because of the weight of the unassisted housing.
In addition to all this with the engine off the steering lock will activate once you turn the wheel beyond a certain angle left or right. So if by some chance you avoided what was on the road your wheel has now locked and you are going off the road.
It amazes me that no one who talks about this pulse & glide knows about these base functionalities in automobiles.
The ABS system or the airbags will not work either by the way. So once you do go off the road as described above the situation only gets worse.
lol..it’s still wrong. its cool man, i know you are trying and are clearly not a nascar fan but maybe just a little research into the CURRENT Dale Jr info would reveal you are looking for 88 not 8. Hope that helps.
To those concerned about P&G in regards to steering and power assist brakes, you’ve made a good point. I forgot to mention it because #1 my personal car doesn’t have power steering so I never notice the difference and #2 I spend so much time mentioning it that in this VERY BRIEF overview, I didn’t think of it.
People doing P&G are not stupid, we know how our cars work, and we don’t advise others to do it before making sure they know also. This post was not an advertisement for P&G, but was just meant to explain how it was employed in racing to to describe what it was for those who didn’t know.
So, Jack, please don’t overreact, and try to refrain from words like “functionality,” which can be defined as “the quality of being of or related to a function.” Function is a much nicer word for it.
Who cares about the darn picture of the car!
Did anyone, who complained of the image, actually GET the story?
I say, put a pic of an F1 race in Monaco or the World Rally Championship in Australia.
It’s the message, people — not the image.
I am curious….. I was under the impression that starting an engine takes about as much gas as allowing it to idle for about three minutes. I can only imagine that in average conditions, P & G would be applying power every minute or less, except on long downhill runs. It would also seem that a manual transmission would be the only way to make this work well.
Subject: using an Earnhardt Jr. pic.
Since this is a news story, using a pic of Dale Earnhardt Jr pic (or his car) falls under the Fair Use.
Fair use covers educational and news reporting purpose.
My impression is Ecomodder is a news/education/news aggragator site. Not some entity that would ‘jack’ earnhardt’s pic and knock out 1,000s of coffee mugs to be sold at $20.00.
P.S. I did ‘get’ what the blog is about: less fuel, more work (distance).
I feel like I have to address this, being a mechanic and semi-long time fanatic of increasing my fuel economy.
When you’re operating your vehicle going down the road, you have vacuum assisted brakes, fluid-assisted steering via an engine driven pump, and several electrical systems that like to be satisfied with energy.
Great. Let’s think about something here, though. You turn the key off, and that engine-driven pump stops working! You lose all vacuum supply to the brake booster! OH NOES!!!11!!
Oh… back in reality, it’s not that much of a problem. You don’t lose brake function, they just get a little more difficult to press. You don’t lose steering, it just gets a little tighter. At speed, in a car which normally has power steering, the steering isn’t really all that difficult when you cut the power. In fact, because of the added effort (which is FAR LESS than 5x more, by the way), the steering of both new and advanced drivers usually becomes much smoother through curves and complex road conditions. Try it one day.
Regarding your brakes – I intentionally removed the power brake booster from 2 of my smaller cars when I had them. BUT WHY WOULD YOU DO THAT YOU STUPID RETARD??!?!? Because there is nothing unsafe about unassisted braking, my friends. If you have the leg to handle the pedal, you can still stop. Again, it stops you from making erratic braking decisions, because you can’t just stomp on the pedal and get wheel lock. You have to apply pressure to the pedal before anything happens.
Regarding the steering lock – No, this is just stupid. Your steering wheel will not lock until you put the key in the “LOCK” position, which is the only position in which you can remove it, in most vehicles. I’m not sure why I’m addressing this, because I feel like if you’re driving, you should already have this tidbit of knowledge. Automatic cars built since possibly the 60’s have an interlock built in to keep them from being put into the “LOCK” position unless the gear selector is in PARK. Manual cars have a key interlock mechanism that requires being actuated before the key can be turned back to “LOCK” and removed. If you turn your car off while you’re moving, you’re not going to lock up your steering.
Regarding airbags not working – Ok, lets be smart. In most modern cars, that have digital sensors that control the speedo, you have to have the key on in order to keep reporting mileage for the time you’ve travelled with the engine off. This would also mean that those same cars have active SRS sensors. Not to mention that your turn signals (which you should be using) don’t work unless the key is on… you SHOULD ALWAYS TURN THE DAMN KEY BACK ON.
I wish people would get their non-sense remarks off these blogs and grow up and learn something before regurgitating information that their neighbors read in some issue of “BURNIN FUEL MONTHLY”, originally meant either in jest or as a means toward an end for the company which originally printed the [advertisement] article.
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