Hypermilers: Common sense or insanity?

The hypermilers' philosophy: squeeze every mile they can out of each drop of gas.

Some of their tips are a matter of common sense and could help any driver, especially now, with gas reaching $3.50 a gallon: avoid jackrabbit starts, use alternate routes to avoid stop-and-go traffic, anticipate lights and drive a bit slower.

But those are just a start. Hypermilers slightly overinflate their tires to cut rolling resistance, seize every chance to coast with their gasoline engines off and sometimes "draft" like race cars behind larger vehicles.

There's more...

• Park at the highest point of a lot, facing the exit, so gravity can help get the car moving.
• Draft off the right rear corner of a tractor-trailer to reduce wind resistance yet allow the rig's driver to see you. Gerdes recommends following the truck at a gap of about 1 second; drafting any closer yields eye-popping gas mileage but is too dangerous, he says.
• Use "pulse and glide": Accelerate to above the speed limit, then shut the gasoline engine down and glide to a speed below the limit. It is fairly easy to do in a hybrid, but in a gas-only vehicle it can be dangerous because power brakes might not work and some automatic transmissions won't re-engage at highway speeds. In a gas-only vehicle, without a lot of practice, "you can wind up killing somebody," Gerdes says. (It's also illegal in many places.)

Did you get that?  They actually advocate shutting your engine off while driving at highway speeds...  tailgating tractor trailers..voluntarily passing up a close parking space.  All to save what?  Less than $.02 per mile driven. 

For my 17 mile commute I would save $.68 per day.  What would it cost me?  I'm guessing hypermiling would add about 5 minutes to my commute.  So it would cost me 10 minutes a day.  But it would also cost untold amounts in public humiliation (does anyone really like to be THAT person in the slow lane), uncertainty over whether my car will restart each time I shut the engine off, the risk of rear ending a tractor trailer and sheesh I might sweat having to walk uphill to my car everytime I leave someplace.  All to save 68 cents a day.  I can't even get a cup of coffeee for that.

Comments

[greg claxton]

All to save 68 cents a day. I can't even get a cup of coffeee for that.

You could probably get a cup of coffee for that at some gas stations, if you bring a re-usable mug. I've been to gas stations that gave the coffee away for free to people with travel mugs. And I didn't even fill up. Of course, there's an irony there, and a true hypermiler would rightfully scorn at making the extra stop.

That said, yeah, hypermiling sounds a bit silly. If you're that concerned with gas prices, find an alternative to driving alone.

[odograph]

I drive "Prius mode" (and 65 mph) most of the time, which is not "hypermiling" to any extreme. It is mostly just looking up the road, coasting down for lights that are red, traffic tie-ups, and so on.

I'm sure the people who jam around me might think they are saving 10 minutes per day, but darned if I don't roll up next to them at that light, 90% of the time.

(They drive hard for that corner case, when not only does the light change, but they have an open lane to take advantage of it. Such behavior is, statistically speaking, stupid.)

[odograph]

OH LOL, a squirrel lived yesterday because I was coasting down for a corner, both slowly and aware that there was no SUV on my ass.

[John Whitehead]

I get a cup of really good coffee a block from my buildingfor a dollar with my own cup. The refill is free so that's a cup of coffee for an average of $0.50 per cup. I could hypermile with Tim's commute and buy a cup of coffee a day with almost a gumball left over. None of those hypermile tricks would work very well on my commute -- up and down with hairpin turns.

[Will]

The Washington Post had a similar article a while back, and included an auto expert's reactions to some of the hypermiling suggestions.

http://www.washingtonpost.com/wp-dyn/content/article/2006/08/03/AR2006080301403.html

This article elides over the most insane hypermiling technique: shifting into neutral into hybrids to shut the gas engine off. Dumb.

[joshua corning]

Hypermilers slightly overinflate their tires to cut rolling resistance

and get less traction...ouch.

but this might be a good point as to why you shouldn't sype (is that spelled right) your tires...great for winter but the other 9 month out of the year you are just eating up gas....

[Thomas]

It might not make sense strictly economically, but consider it as a hobby. Not everything people do is justified by economy.

[Kevin Heist]

This is the most ludicrous concept in the history of the automobile,and what's worse is that it's being presented as fact,when it's fiction at best.Being a formerly licenced technician,and still employed in the service dept of a Toyota dealer,I can tell you that shutting off a hybrid engine completely defeats the whole idea of having a hybrid in the first place. And "drafting"?? Works well at Daytona at 190 mph,but at regular highway speed,it's a complete non-factor.Some buffetiing and turbulence may occur,but at 60-70 mph there is absolutely ZERO effect.Maximum air pressure in the tires? Definitely not recommended since having the centre of the treads of the tires bearing the load of a vehicle that's not loaded down(the reason for max pressures)is not only unsafe,but patently stupid.The quack that began the site needs to be shut down before somebody gets hurt,since none of theses practices actually work,and all are a detriment and hazard to the unsuspecting drivers on the road.Perhaps a lawsuit would be in order...

[Mandragoran]

Could you give us a little more detail about the source of that information? e.g., have you tried it, with a vehicle with a running gas mileage indicator, and confirm that there is no increase in the displayed mileage with drafting? Or, have you tried it without such indicator and not noticed that you have to back off on the gas to avoid running into the truck? Or, has somebody published a paper about that in a peer-reviewed journal?

There is no doubt that drafting on the highway, especially behind trucks with no visibility, is dangerous. But, at highway speeds, isn't most of the power used (on a level road) for overcoming air resistance, not rolling friction? There can be little doubt that the air resistance is much less in the first few feet right behind a big truck.

And, if drafting doesn't work below 71 MPH, why do the bicycle racers do it?

[Rob]

He clearly hasn't tried it and has no data to support his contention. It works without question. Further, it can be done safely. See:

http://hamiltonianfunction.blogspot.com/2007/06/blog-post.html

[Jim]

Kevin Heist should do a little more research before he shoots his mouth off. It's been proven that drafting at freeway speeds greatly increases fuel economy, even staying back at safe distances. Also, running your tires at slightly higher pressures only makes the ride more harsh. They're not talking about filling them so that the centers pop out. Grab a clue.

[Kevin Heist]

Grab a clue Jim??? Funny,coming from someone who doesn't have one.My clue,is my vast automotive experience,coupled with my techician's licence,neither of which the originator of this ridiculous practice,or anybody else on here,has. Even a 10% increase over recommended tire pressures,has a huge negative impact on overall vehicle stability and tire wear. How much fuel do you have to offset the cost of replacing 4 tires every 20,000 KM (12,000 miles)??
And for the record,yes,I have "tried it",with a handheld tester interfaced with the PCM which shows in realtime the current actual fuel mileage. The result?? At highway speed 100 KMH (62.5 MPH) the "drafting" gain showed the difference as 9.3 litres/100km (31.6 mpg) to 9.2 L/100 km (32 mpg)--hardly a substantial gain. To answer the question,no, most HP isn't used to combat wind resistance (90% of cars today have a .32 cd-that's drag coefficient-or less--very tough to improve on that at all)or rolling resistance,but rather momentum. Simply put,you're trying to keep something rolling that wants to stop.
Yes bicycle racers and go-kart racers "draft"--but just because they're doing it,doesn't mean it's working. It's not. Not enough air is displaced by a human to create the vacuum effect known as drafting. Still not convinced??Then use my previous NASCAR example-at Daytona or Talladega at 190 mph,the draft is fairly effective. At Bristol,or Martinsville at about 90 mph,zero effect.Any driver will tell you that. I reach speeds of over 110 mph at my local oval track,and feel no drafting effect at all. What makes you think your econobox at 70 mph on the interstate is any different?. It amazes me what sheep people really are,and from experience,most of them are import drivers.

[Danny]

When I recently tried some of these hyper miling techniques I got 2 mpg better on my last 1/4 tank of gas. I can only imagine if I used it 100%. Not to mention the previous 3/4 of a tank was spent stuck in traffic and letting me wife drive. She has a lead foot, accelerates hard from a stop, and doesn't ever keep a constant spped

What is safer? Being completely aware of your surroundings (which you have to do by hypermiling) or driving 10 - 15 miles per hour over the speed limit, talking on your cell phone, eating, or drinking which most people do while driving. I know Mythbusters (they are not perfectly scientific but hey...) did a test both on tailgating a semi and talking on the phone while driving. The semi test gave you better gas mileage if you could maintain constant speed and the cell phone test was comparable to drunk driving.

So what should everyone do? I say SLOW DOWN to the speed limit and PAY ATTENTION.

Also there are other methods as well that save gas and money such as car pooling, public transportation, riding your bike...

If I can get 8 MPG better using it 100%, I think it's worth it. but seriously for that last 1/4 of a tank, I just slowed down and did 5 under the speed limit, didn't accelerate from a stop and coasted to the stop sign/light. I tried not to use my A/C as much as well. Those were the techniques I used which is not even hypermiling, just common sense.

oh yeah, maybe, just maybe 68 cents a day will add up, since around 171 million Americans drive cars. let's see $.68 x 171 million = $116,280,000 per day. Seems worth it...?

[bmw]

Kevin you are right on the nose. I commute 200 km every day on the highway. I've tried following trucks at 60 mph at distances varying from a car's length to 100 metres. There is no difference in gas savings except buffeting, additional stone chips thrown up, and an increased tension from tailgating.

What I've found is with a 6 cylinder car at 3 000 rpm 60-70 mph nets a 20% fuel savings which averages to about $25 per week on gas saved for me

If there was a strong headwind of over 30 km/hr then I might change my mind, but I think the decreased fuel economy is largely from higher rpms in the 4 k range as seen at 80 mph the most popular speed on the 401

hypermilers have a good idea coasting, using their brakes less and keeping a nice braking distance.

but I wouldn't recommend going under the speed limit even though my best fuel efficiency at nearly 40 mpg is achieved at 80 km/hr or about 50 mph going down or uphill

[Danny]

For BMW,
I was just wondering the point of the speed limit if you not supposed to go under it? It's not a speed suggestion. Do you think we should just drive as fast as we want?

Every Monday and Tuesday I drive 80 miles round trip. Today, I went 5 miles under the speed limit, 65 in a 70, and got to my destination at roughly the same time I would have if I went over it. I can't figure it out, the time issue, but I did save some gas. I really could care less about the "embarrassment" factor. I just think to myself about the pennies I'm saving.

I also noticed what ODOGRAPH saw...
"I'm sure the people who jam around me might think they are saving 10 minutes per day, but darned if I don't roll up next to them at that light, 90% of the time."...I wave to them, if they give me a dirty look for not quickly accelerating off of the previous stop light.

If I go 70 MPH my RPMs, I usually stand at 3,200, but 65 is usually about 2,900. Also, this is my first full tank since using the techniques I mentioned in my earlier post. We shall see how my MPGs look at the end of the tank. I would rather have 45 MPG than 36 MPG (avg). Wouldn't you?

[Stephen Remes]

http://www.gassavers.org/showthread.php?t=5623

Seems like this guy had some results using a scangauge

[Kristin]

Hi boys, I have a 2001 Hyundai Tiburon and even just some minor adjustments to my driving got me more mile for my buck. I try to stay behind a semi or large truck on the highway at a 2-3 car distance, time my traffic lights and try not to brake whenever possible. My engine oil and psi in my tires remained the same and in the past 2 tanks of gas I have gone from an average of 28mpg to 32.5mpg. That's 390 miles on 12 gallons without all of the unsafe aforementioned techniques and only half of my travels are on a highway. Since I'm new sometimes I even forget to use the techniques, can't wait to see my mpg when I'm master of the methods. Maybe the Tekkie Kevin prefers to sponsor the hostilities in the middle east with his gas dollars but not me. I'm keeping as much of my money right here at home, out of the Saudi/Arab oil billionaires giant pockets

[Kevin Heist]

I'm all for saving fuel whenever possible (hence the reason I took a 4 cyl car from Ontario to Virginia and back this weekend),I'm just not impressed with silly,gimmicky and patently stupid and unsafe ways of doing it. Driving smartly and efficiently will net the average driver a visible savings,without having to go to ridiculously unproven and baseless extremes.