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In my post on hedging gas prices, reader J.P. introduced a concept that I had never heard of before – hypermiling. Essentially, there are a group of people out there so serious about improving their fuel economy that they are swapping data and tricks in order to wring every last MPG out of their cars. Users proudly post pictures taken of their fuel economy meters. Imagine, treating high fuel economy as a competitive sport!
Although many hypermilers manage to wring out over 100 miles per gallon out of their hybrid cars, many of these concepts can be applied to non-hybrids as well. It is very intriguing to see the many different behaviors that they describe. The following are taken from this thorough article on CleanMPG.com as well as the Wikipedia entry on hypermiling.
Basic Tips
First up, here are some of the more conventional tips that you might have read about elsewhere. Most of them follow common sense; if you make your engine work harder, it burns more gas.
- Do not use quick accelerations or brake heavily.
- Do not drive at higher speeds.
- Combine trips to reduce driving with a cold engine and on frequent short trips.
- Remove excess weight and/or cargo racks. Do not tow unless absolutely necessary.
- Minimize running mechanical and electrical accessories (e.g. air conditioning).
- Avoid driving on hilly or mountainous terrain if possible.
- Do not use 4-wheel drive if it is not needed.
In practice, this means driving very differently that you might now. You want to accelerate your emptied car as slowly as possible, and continue to drive as slowly as possible once you go past about 30 mph, especially on freeways. You want to be aware so that the second you may need to stop or can coast, you can take your foot off the gas pedal immediately. Don’t use air conditioning, do use cruise control. Track your mpg with a mileage log to measure any improvements. (Most people do not ever achieve the given EPA fuel economy ratings for their vehicle.)
Advanced Tactics
Here we get into some more extreme behavior. Note that not all hypermilers engage in these activities, these are simply the ones that push the envelope. Some may be considered dangerous, or even illegal in certain areas.
- Use an real-time fuel economy meter. If you don’t have a hybrid with a built-in meter, get yourself something like the ScanGuage II.
- Inflate tires to much higher pressures. Higher tire pressures -> Lower rolling resistance -> better fuel economy. They recommend not just inflating to the psi recommended by your car, but the maximum sidewall rating allowed by your tire manufacturer. Some members even take advantage of the “factor of safety” that engineers use and pump it up to 25% over the max rating. 50+ psi is not unheard of.
- Switch to a special motor oil. Using low kinematic viscosity oil helps improve mpg.
- Forced Autostop: Turn off engine whenever possible. If you’re slowly stopping to a red light or just coasting, turn off your combustion engine completely (“force” it to “stop”). Keep the engine off while idle, and only start it up when you’re ready to go again. This reduces losses due to running the engine at idle.
- Pulse and Glide. This consists of driving using alternating periods of accelerating (“pulse”) and coasting (“glide”), and then repeating the process. It is most efficient if you turn off the engine and coast in neutral while coasting.
- Draft behind big rigs or large vehicles. Take advantage of the turbulent air behind a big rig on the freeway by driving as close as you feel comfortable behind it. The resulting lower air drag means you need less gas.
The Financial Payoff
Although many hypermilers have other motivations like less fuel-dependence, better environment, or simply competitiveness – another obvious benefit is in fuel cost savings. Reports indicate that improving your fuel economy by 30-40% is definitely possible without using all of the advanced tactics. If you went from say a combined city/highway 22 mpg based on your previous habits to 30 mpg (a 36% increase), and you drove 12,000 miles per year with gas at $3.70/gallon, this would save you $538 over a year. Worth it? Your decision.
Personally, I like learning about people who take anything to the extreme, that way I can just pick and choose what I want to implement in my own life. I think I’ll go check my tire pressure tomorrow…
How much do your tires cost? How much do you value your life? Your tires are engineered to give maximum traction at their recommended pressure. Anything higher than that bows out the tires, decreasing the amount of tread on the road, and therefore reducing traction significantly. Additionally, this is compounded by the fact that those spots will wear down much faster than the rest of your tire, and give you even less traction. So, not only will you need to replace your tires significantly more often, but you’re endangering your life and the life of everyone around you on the road. Bad idea.
Same goes for turning off the engine while driving – you no longer have power steering or power brakes. If anything should go wrong, you would never be able to react fast enough to avoid the situation. This is even worse than the above. Yes, if you’re sitting in gridlock, turn off your car. If you’re sitting at the curb waiting to pick someone up, turn off the car. But not while the car is in motion, it’s incredibly dangerous.
Dragging behind bigrigs is fine as long as you give yourself enough room to stop. The recommendation is 2 seconds between you and the car in font of you. That’s a pretty long way at highway speeds, but Mythbusters did a test and you got a decent bump in mileage even that far back. Moving up closer is again dangerous and likely to cause an accident (and when you get in an accident with a big rig…. you lose).
I applaud the idea, but many of these things are just plain dangerous.
Nate, I completely agree these tactics are quite dangerous to save a few bucks (if any at all). I think by the end of your year driving on 50psi tires would have worn your tires out adding an addition $600 for good high mileage tires, turning your engine on and off during costing periods will have ruined your ~$150 starter and using too low viscosity oil will reduce the life of your $3000-4000 engine. Neglecting the engine entirely you wind up losing $212 by the end of the year.
A better solution would be to look at your vehicles BSFC (brake specific fuel consumption) and trying to operate your vehicle in the RPM range where you maximize power and minimize fuel consumption. This usually lies between 1700-2200 RPM, but it varies for every engine. This way you’re not a menace to everyone else on the road and still getting better fuel economy.
Just use common sense.
You just used the words “kinematic viscosity” in a blog post. I have officially broken out in a cold sweat. Do I have a mechanical engineering test in fluid dynamics today?!!!
Turning off engine while the car is moving is a very bad idea because you do not have full control of steering and brake !!!
You don’t mention alot of the more stupid techniques these guys use. For example, pulling into a parking lot and just coasting the car around to bleed off speed and roll up the odometer. Sure it’s great for their stats but does nothing to actually save gas. Someone who just uses the brakes and pulls into the first available spot will use the same gas but not roll their odometer as high. Choosing a longer but more level route might result in higher MPG but use more total gas to get from A to B than the shorter route with more terrain. Also, drafting behind trucks is penny wise but pound foolish. In addition to the horrible beating your car will take from rocks that get kicked up by the truck, eventually you’ll get hit by something larger that falls off the truck like retread.
Smooth acceleration and braking seem to have the biggest payoff in my experience. My car is rated 27/34 and I regularly get 30/38 using this method. It also helps to have a manual transmission. Inflating tires to crazy high pressures will make your ride extremely rough and possibly have the opposite effect due to more bouncing over bumps rather than allowing the tire to deflect somewhat. I usually pump mine to about 35-37 psi which seems like a good compromise.
Ever been right behind someone who was 100 – 150 yards behind the car in front of them, while traffic is laboring along at an average of 10 mph? Then traffic speeds up around you and you’re still laboring along while the space in front of the car ahead of you continues to grow. You were probably behind a Hypermiler.
I read some posts about this two months ago and i thought, ‘how great — these people are saving a few dollars for themselves while single-handedly creating more pollution by slowing down ALL the cars behind them.’ All they’re doing is increasing the amount of time ALL vehicles behind are on the road, not just theirs.
Hypermiling can be great if you’re in rural parts not prone to commute gridlock — i even used the draft behind large trailers technique on a couple cross-country road trips, and i usually slow gingerly to stops when nobody’s right behind me which also helps to preserve the brakes — but these practices need to be kept off popular freeways like our Bay Area highways. Any hypermiler who’s holding up the line behind them is just as selfish as the bum in your rear-view mirror who’s riding your tail, if not more selfish.
All that work to save under $600.
I couldv’e saved more if I stopped myself from purchasing an Xbox360 and Nintendo Wii last year.
Being Frugal is something I’m a huge fan of, but when it comes to fuel the only method I follow is dont slam on the gas,drive only when nessesary, and plan errands together so it’s in one trip.
I’m betting the majority of these fuel economy peeps who are taking pictures of their fuel gauges, likely do not need to take these drastics measures to save money. They rather due it as enviromental reason or a hobby.
For people who need to take alternative measures for economic reason, fork of the money for gas and drive less, eat out less, buy generic brands.
Oh and go on craigslist and buy my WII
“Turning off engine while the car is moving is a very bad idea because you do not have full control of steering and brake !!!”
This is not true. The technique involves shifting the transmission to neutral, turning off the ignition to IG-1 so that the motor turns off and then quickly turning the key back to IG-2 so that the steering is not locked. While in this mode, you do not have power steering, but you do have power brakes for at least a few applications.
Before anyone runs out to try it, I recommend practicing the technique in an empty parking lot and understanding fully how to implement it and how many brake applications before the vacuum runs out.
Please do go to CleanMPG and read up on all the various techniques and ask questions in the forums. There are a lot of helpful and knowledgeable people there.
Using some hypermiling techniques, I went from getting 33 MPG driving conservatively to 42 MPG hypermiling. My vehicle is rated 25 city and 35 highway.
@ Phoenix – but don’t you think that you can drive more effectively (and peacefully) in gridlock by leaving a nice buffer between you and the car in front of you? When they stop abruptly, you can keep coasting a bit – it allows you to maintain a lot more of a constant speed and avoid a lot of the stopping/starting nonsense as well as wasting gas. Obviously if traffic picks back up most people want to speed back up, for safety as well as courtesy to those around you. But I think that in moderation this sort of technique can be quite useful.
Phoenix, your assertion is absolutely not true. First, the typical hypermiler would generally avoid rush hour stop and go traffic like the plague. Second, by keeping a buffer in front of you and driving smoothly without braking in stop and go rush hour traffic, you are smoothing traffic flow and simply averaging the speed of a quick acceleration and slamming on the brake. Third, hypermilers are concerned about road safety and not impeding others.
yeah seriously. just a pet peeve I suppose but if someone’s is conserving gas by holding off on abrupt and sudden acceleration.. stick to the slow lanes please. I’ve seen plenty of prius do this in so-cal, and I know exactly why they’re doing it… and it can get pretty annoying if you’re stuck in a wolf pack because it.
still, never knew there exist a subculture of “hypermilers” etc. learned something new today.
I keep my tires properly inflated by checking every 2-4 weeks, depending on commuting time for the month, and I clean, wash, and re-oil my K&N oem filter replacement every month… that’s about all I do to keep my mpg to a reasonable level (besides other usual regular preventive maintenance).
if I drive at a brisk pace, I do about 31-33 mpg. if I drive conservatively, I can pull ~37 in my 5spd civic. either of which is good enough for me!
I’d rather not tailgate large trucks. It’s a great way for one not to have any idea of the road conditions ahead (i.e. accidents, stopped traffic, pot holes, other debris, etc.).
Not to mention when one of their tires sheds a layer of rubber and shoots it right at your car at high speed. The damages caused kind of negate the gas savings.
I’m sure the semi drivers love it when you hide out of view of their mirrors too.
I concur with fortune8. If one has power steering and power brakes, turning off the engine while moving is a bad thing. It will become a very bad thing if, for whatever reason, something happens in front of you and you need to stop, slow, or take evasive action to avoid a collision.
As for “pulse and glide”, I’m curious how this saves fuel. You use more fuel when accelerating than when traveling at a constant speed. You burn lots of fuel to accelerate then save it when coasting. Maybe if you turn off the engine while coasting you may gain a little in the MPG. At the very least, it will tick off the person behind you who wants to use their cruise control but have to feather the accelerator due to the car ahead of them not being able to maintain a constant speed. As a result, other people burn more fuel while you save a few MPG. You jerk!
As for turning off the engine at a red light, I do this myself, but since I don’t want the car behind me to drive his car into my trunk, I only do it when 1) I know it will be a long light and 2) I am a couple cars back so I have a second or two to start the car before the car behind me expects me to move. The problem with turning off the engine at all red lights is that when one is at the front of the line, and the light turns green, the car behind will assume that the lead car is ready to go and start moving. This is a recipe for disaster.
I would like to get a ScanGauge II. I don’t know how useful it would be or how I would mount it in my car, but it would be interesting to see what my real-time stats are.
Overinflating your tires sounds kind of dangerous to me. Yes, I know there’s room above the recommended amount, but that’s for your safety. Of course, I think riding your brakes is a bad idea, but I wouldn’t purposely limit my brake usage to save gas. I might slow down a bit, I do tend to take off at lights (after they’ve turned green ;>), maybe I could loosen my foot up a bit. But yeah, I’ve got to say, nothing is quite as annoying as someone Sunday driving in front of you, especially during rush hour. I can feel my blood pressure rising, and I try to ignore them but it would be nicer if they just pulled over and took a nap and waited for everyone else to get to work before they drove like that.
DB: I think phoenix is mostly talking about after a gridlock area is over or ending.
personally I have no problem with people leaving 2-3 car spaces between them and the car in front of them, if we’re in a gridlock (after all, where else can any of us go?) but when traffic picks back up and average speed around us increases 10+ mph, I think I’d appreciate it if they up the speed too.
or, change to a lane that conforms to the speed they want. based on three sec rule, 100 – 150 yard when traffic is at an average of 10 mph in a gridlock just sounds ridiculous. that’s way beyond safe following distance. 100 – 150 yard is plenty even for 65-75 mph in good driving condition.
>>>Draft behind big rigs or large vehicles. Take advantage of the turbulent air behind a big rig on the freeway by driving as close as you feel comfortable behind it. The resulting lower air drag means you need less gas.
This is called tailgating and is illegal here in Michigan (besides being simply rude and stupid).
Just a quick heads up about the “FAS” (Forced Auto Start).
DO NOT DO THIS IF YOU ARE A HYPERMILING NEWB.
When you kill your engine, on many transmissions (non hybrid car transmissions) you also kill the pump that is circulating transmission fluid. Without the fluid circulating, the transmission will continue to get hotter and hotter and you run the risk of metal-on-metal contact in your transmission. That’s very, very, very bad.
Before attempting something like FAS or Draft Assisted Forced Auto Stop (DFAS) make sure your car has a transmission that it is “flat towable” (which means it can be towed with all four wheels on the ground).
Otherwise, the best you can do is to shift your car into neutral for a much better pulse and glide. And even then, if your car has built-in fuel conservation technology like the Ford Thunderbird, where it will turn off the fuel injectors when coasting or drifting downhill, putting it in neutral will actually give you worse mileage.
You really need a realtime mpg gauge to hypermile correctly. If you’re interested in doing this, get a ScanGuage II and read up on the websites before attempting on your own.
Violating traffic laws, safety recommendations and generally endangering everyone driving near you? To gain a few miles per gallon? That just sounds stupid.
Besides, how much will your insurance go up when you rear end someone because you had your car turned off and didn’t have power brakes?
Although doing some things when driving can improve gas millage significantly, don’t anything that puts you or others at risk. Focus on the basics: accelerating smoothly and gradually, coasting to stop for the red light ahead (don’t speed up and then have slow down), and keeping enough distance between you and the car in front of you so you don’t have to slam on your brakes constantly.
Serriously, I am not a litigious person, but if I were in a collision with someone and I found that they were doing any of these “advance tactics”, I would be after some serious compensation.
“…and continue to drive as slowly as possible once you go past about 30 mph, especially on freeways.”
Suicide.
If the road is at capacity, I’m not so sure the hypermilers make a difference:
http://technology.newscientist.com/article/dn13402-shockwave-traffic-jam-recreated-for-first-time.html
That said, I question some of these practices for safety reasons (tailgating trucks, over-inflating tires, turning off the engine while moving). Also, I’ve always understood that if you end up having to open the windows in order to turn off the AC the reduced aerodynamics cost you more gas-wise than just leaving the AC on, though I’m sure this is vehicle dependent.
DO NOT OVERINFLATE YOUR TIRES!!!
Was that loud enough? Repeat — do not overinflate the tires. Unless you want them to blow up, that is.
“Forced Autostop: Turn off engine whenever possible.”
Won’t this also turn off power brakes and steering? Not a good look.
Be careful about switching off your engine while rolling. Manuals are okay but some automatics don’t get any lubrication when the engine is off so you’re really putting some wear and tear on them. If your owner’s manual says you can tow your car with four wheels on the ground then you’re safe with this technique, otherwise I’d pass.
Unless you’re towing or carrying heavy stuff, max sidewall pressure on your tires is fine. It’s a rougher ride, you’ll get more road noise, and if your car is getting on in years – more rattles. I’ve been at close to max sidewall for 2+ years and never had a problem (I’m a lil under it only because I don’t trust the built-in gauges at the public air pumps). On my car its an extra 10psi from what’s on the door to where I usually put it and that is still leaving some room for gauge errors from max sidewall.
fortune8: I do the engine-off thing sometimes. Only power steering is really affected (and that’s pretty severe, make sure you know what you’re doing before trying it!). power breaks aren’t as big of a deal. You’ll lose ABS, but that’s never needed unless something really bad is happening, and you’re hopefully not turning your car off while moving when there’s enough traffic around to make that a possibility…. But anyway, you still have “full control”, just not as powerful as you’re possibly used to 🙂
Anyone know if “clutch-coasting” (lowering RPMs by disengaging the clutch while moving) is more or less fuel efficient than simply not touching the accelerator?
There was an episode on Myth Busters a while ago about true fuel savings while trailing big rigs.Their conclusion was that there was an appreciable reduction in fuel expenditure, but the risk of trailing a rig makes it not worth it.
I have 4d Kia Rio and it was averaging 27 mpg. I rotated the tires, replaced the air filter and drove like an old grandpa to get 31.5 mpg. That almost saved me an extra gallon of gas. I do not look at my tank gauge to see when I need to refill, I look at my trip odometer.
Wright: Yes shifting to “N” is better than just letting off on the gas as now you’re not wasting energy turning your transmission around. It’s not as good as turning the engine off technique since your engine will be idling and sipping a lil gas in “N”. I used to do this on my old car not to save gas but because it was old and it idled alot smoother in “N” than leaving it in “D”. My problem with this is, it’s so easy to do I sometimes forget to put it back in “D” to get moving again.
Thanks Max! I’m glad someone said that! The danger of overinflating your tires is not so much that they will explode while you’re inflating them (though that it possible, and life threatening), but that they will explode while you’re driving on them, at say 65 mph. Think about it, tires get traction through friction with the pavement, friction generates heat. Heat increases the pressure inside the tires, so if you start at ambient temps at 40 psi you may have 60 psi after you’ve driven around a bit.
Also, the added pressure bulges the tread of the tires, causing you to drive on a thin bit of rubber in the center of the tire. This increases wear in the center of the tire and reduces the size of the patch of rubber that is in contact with the road, reducing your ability to brake, accelerate and turn. This is a seriously bad idea!
What do you figure happens when you tailgate a tractor trailor on the highway while driving on overinflated tires and have to slam on the brakes to avoid an accident? I bet it costs more than a few gallons of gas!
I’ve been driving with some of these techniques for about two years now—but not at the expense of safety, so I won’t hesitate to brake abruptly or accelerate quickly if the traffic demands it. My 1993 Toyota Camry averages about 36 MPG now, compared to about 30-31 MPG before I started driving this way. So I save about $250-$300 a year, which is a lot for my low paying job and tight budget. I actually see that as a plus since I’m more conscious about my environmental impact.
I would not recommend pulse and glide unless someone with the appropriate background could explain why that would work.
My hypotheses is that it either works by the placebo effect or by lowering your average speed. it would be better to just drive consistently at the average speed that pulsing and gliding gives you.
There may be some savings by coasting down hills but you would have to have a pretty steep hill.
btw, my 2003 Jetta TDI achieves the EPA rating. I have a 47.5 US mpg lifetime average for a little over 2 years and 40,000 miles. It will run around 49 in the summer and 44 in the winter.
Mark, there is no ‘placebo’ effect as you pulse and glide most of your driving life. Ever hear of stop and go traffic? But the thing here is that your engine is off, so you are not using gas for most of your trip. Has mythbusters covered this one? I don’t think so.
Personally I don’t do that exactly, but I do shift into Neutral most of the time while leaving the engine running. I have seen that that alone will give my minivan an extra 5 mpg on average (pretty good since my minivan only gets 20 mpg). I don’t trust tailgating and I hardly ever drive in ‘traffic’ so the Neutral route is pretty much my only thing. The engine will drop to almost half the rpm, still leaving the AC and power everything going, and all it takes is a slight pressure on the shifter to put it back in drive when I need it. After you do it a while, it becomes second nature.
I don’t know if any of you have watched the mythbuster’s show where they showed that driving with your air-conditioning on and the windows up can be more efficient than driving with windows down and air-con off. I had come to the same conclusion since the airodynamics of the van were such that when I put the windows down I would have to step on the gas to compensate. Next time you are out driving, turn your AC off and be conscious about your foot on the accelerator when you open the window. Do you slow down or do you ‘instinctively’ press down harder?
Draft behind big rigs or large vehicles ?
Bad idea in my opinion. I have gooten my windshield broken from stones thrown from big rigs in front of me.
I’ve always been told that one uses more fuel starting (igniting) the engine than is used, for example, if the engine idles for one hour. Doesn’t it make sense that more fuel needs to be injected during ignition to get the engine up to the proper rpm (0 RPM to 2000 RMP) v merely maintaining a 2000 rpm?
Bottom line is that I don’t know how turning off your engine and starting it again is more efficient than just idling for a min. or two.
I’m sure there is a good website or two that discusses this. Maybe a myth busters? I love that show.
Kid Z: this is an urban myth:
http://www.popularmechanics.com/automotive/how_to/4205233.html
Alex
@KidZ
Cars have far more efficient starters these days. My rule of thumb is if it looks like I’ll be idling for at least 20 seconds, then it’s worth turning off the engine. I also time most every traffic light on my route to/from work and know their patterns, and will also key off the pedestrian walk/don’t walk signals.
@Phoenix
Those who, while in traffic or otherwise, accelerate too quickly, follow too closely, and brake too frequently, are doing far more to disrupt traffic flow than the hypermiler or anyone just trying to smooth out their speed (and that of overall traffic).
Cheers,
On my trips around the world, I took some scary rides taxi drivers practicing hypermiling on their old and runned down cars even 10 years ago. In Egypt, they turned off the light while driving at night, and only turn them on before making a turn.
In Equador, a taxi driver turned off the engine while going down the hill, I must say this scary especially since the cab was way over-crowded.
I guess the US are just catching up with the rest of the world in techniques to save on gas.
I live in Atlanta and frequently drive to Jacksonville, Florida for business. I have made the trip there and back over 100 times and have tracked gas mileage each time. On the trips that I got in behind a big-rig for the majority of the trip, my Toyota 4-cyl Camry got 39-40 miles per gallon. On the trips where I did not do this, I only averaged 33-34. Having said that, I never got behind a truck that didn’t go at least 5mph over the speed limit, which is what I drive 95% of the time.
I’m all for extreme ideas, but turning the engine off scares me a little. I mean, it probably makes sense to turn it off when you’re stopped a red light and you know you’re going to be there for a while, but I’m not so sure about the pulse and glide thing. I suppose I should mention that I live in Los Angeles and I’m convinced that most of the drivers around me are well-disguised orangutans (at least everyone behaves that way, including me when I lose my patience). Maybe I’m just chicken, but I’d be scared that I’d be forced to react quickly to something and find out… oops, my engine’s off! I really don’t want to spoil the party since I think these creative ideas are great, but not having control over my car would sort of freak me out.
Definitely a pick and choose type of thing. 30 MPH on a freeway? Do you want to die? I wouldn’t survive a week. Of course, 55 MPH would work and it is the last sweet spot before your mileage really goes down hill due to speed.
I didn’t see any info on reducing weight. I plan on removing the back seat of my camry soon, as I have never used it for a passenger in 5 years. I will also ditch the floor mats, carpet in trunk, and anything else I can think of that will come off easily. I care nothing for how the car looks. I read that 100 pounds saves up to 4%. I can also lose 20 pounds which makes a better incentive than most weight loss plans I’ve heard about. My health? Who cares. My wallet? Now you’re talking!
Speaking of AC I’m going to have that removed as well. The unit must weigh a lot and we don’t need AC in Oregon. Can anyone else recommend something that can easily be removed from a car?
I plan on storing everything I take off and will put it back if I ever resell, which, as I’m frugal, I hope never to have to do.
I ride my bike and get infinity miles per gallon. a human on a bike uses 30 calories to travel a mile. a human walking uses 100 calories. A car uses 1000 calories. (you can actually save enough energy to produce the bike and account for the resources that go into the making of the bike)
A human on a bike is the most efficient mode of transportation in the known universe.
happy bike to work week everyone!
Really. Drive around less. Try taking a bicycle. If you have to drive, drive a stick-shift.
I’ve tried some of the hypermiling techniques and frankly, I find most of them to be really unsafe. At most, I drive with an open clutch on downhills, coast up to red lights/stops and I turn off my engine at long red lights (of which I have few on my reverse commute on an interstate highway).
The main thing I’ve heard is to keep your engine RPM’s at a constant. Since I drive a manual I can see my tach and what level I am at. I guess I’m not doing it right because when I’ve tried hypermiling, it doesn’t seem to make a difference.
I learned at a young age to drive my car and shift by SOUND rather than by RPM’s. When I can hear the car needs to shift when I’m accelerating is when I shift. Rarely do I ever go up past 4000 RPM’s unless I am going A) 70-80mph in my top gear on long interstate trips or B) I’m stomping on the gas for whatever reason I’ve deemed necessary. With those habits, I used to get 31 mpg on long road trips and 27mpg on my mostly highway commute. City driving is tougher and I get usually about 24mpg. But my car’s official test lab ratings are 31 mpg Hwy, 23 mpg City, so I am doing pretty darned well just the way I am without wacky techniques.
I say ‘used to’ because my car is now 8 yrs old and recently I seem to get about 29-30 mpg on long trips and 24-26 mpg on city driving and can’t seem to get back to 31 mpg again.
Cruise control doesn’t seem like a good way to increase MPGs as most cars when you go up and down inclines theres an unnecessarily strong acceleration/deceleration to try and match your fixed speed. On a flat road its a different story.
Mark,
The reason why pulse and glide works is because a gasoline engine is most efficient at near full throttle. So you accelerate with near full throttle (low RPM though) and then coast in neutral for a while until it’s time to accelerate again. Your diesel is different, not subject to throttling losses so pulse and glide will probably not help your car.
People who are saying to accelerate gently are just wrong. I use 90% throttle almost all the time and average 45 mpg in my Yaris which is rated for 36 mpg in the city. I use pulse and glide often, but usually just between stop lights. Doing that on a long road trip would drive me insane.
Stopping abruptly does not matter either, but you should try to drive like you don’t have brakes. Every time you push the brake pedal you are wasting fuel. If you do need to stop (like when a light suddenly turns yellow), the rate at which you stop has no effect on fuel usage. Your engine is idling the whole time regardless and does not care how fast the car is stopping.
I learned how to drive for MPG by using the ScangaugeII. It has paid for itself many times over in fuel savings and it’s fun too! Not only that but I’ve used it to reset the “check engine” light.
Hypermiling techniques are much easier with hybrids since the engines can go into FAS mode by just applying the right amount of pressure on the gas pedal. In addition, pulse and glide in traffic is possible by making the cycles shorter — e.g. instead of 5 seconds acceleration + 25 seconds glide, do 1 second acceleration + 5 seconds glide.
I would not be comfortable using many of these techniques in a gas car though.
Well, I went the different route (since I was already doing all I can to decrease my mileage and there was nothing else that could be done) and bought myself a 50cc Yamaha scooter. It gets 117 MPG, it goes 40 MPH and it’s bulletproof. Take that arabs and chavez (not worthy of capital letter)!
Albrecht- you really could’ve kept that last sentence to yourself.
Quick – you’re making a flawed generalization. Increased traffic is caused by increase in the number of vehicles in a given space. During times where there are more cars, if you increase the space between cars then you have more cars squeezed into less space, thereby slowing those cars down even more.
For example, if there are 200 cars at any time going through a 1-mile stretch of road with 2 lanes of traffic traveling in the same direction. Break up that 1 mile stretch into 2 half-mile stretches with 100 cars going through each half. Now, if a bunch of cars in the first half begin increasing the distance between themselves and the car in front of them due to practicing a form of hypermiling (because the traffic is not all traveling at a constant speed) at some point the space in the front half-mile is not enough for 100 cars and now 20 of those cars are the back half-mile stretch of road. So now you have more cars in the back confined to less space, ie – MORE CONGESTION.
With traffic, there are many different driving habits and many different cars with various acceleration capabilities. I’d be much less aggravated being behind someone driving a 1980 corolla who takes a long time to accelerate to the going speed than i would being behind a 2007 vette that takes the same time to get to the going speed as the corolla. But being behind 20- or 30-something driver in a vehicle that’s less than 10 years old who’s accelerating at a fraction of the speed as the surrounding cars is very aggravating.
Well, I’ll definatelly think about that
http://money.cnn.com/2008/05/12/autos/ways_to_not_save_gas/index.htm?postversion=2008051315
pheonix,
I think I agree with Quick.
when you increase the space between cars, you are not squeezing more cars into less space, in fact there are less cars in more space. This is the reasoning that has led to traffic lights at on-ramps. Its an effort to create space between the vehicles, thereby improving the flow of traffic. Your point is valid, that if only half of a section of a two mile stretch of road were to change behavior, it would increase congestion in that area.
My gut tells me that not every person will begin to stop being a maniac driver and give everyone space, so I will continue my practice of driving like a chilled out hippie or grandmother, while those immediately behind me in vehicles taller than my car will continue to fume and rage. I guess I find it amusing at how rapidly their frustration rises.
Semi’s control traffic this way all the time. They leave large spaces in traffic to facilitate movement. Sometimes they block both lanes and work to smooth out traffic. Usually they tend to take breaks during rush hour.
I have owned a hybrid for a year now with all the fancy gas mileage stats. I have learned a few things which I now make sure to do while in my non-hybrid vehicle.
Drive 55 mph whenever it is prudent to do so, which is the speed at which nearly all vehicles operate most efficiently. Also, reducing your braking by letting the engine slow down the car is the single best thing you can do to prevent wasting fuel. Last, change your air filter religiously, use the lowest weight oil you can, the exact octane fuel recommended by manufacturer, and properly inflate your tires. This are the only things that work for everyone all the time, in all driving conditions. Car manufacturers spend millions testing their vehicles to learn ways to optimize fuel efficiency – they publish these results in the owner’s manual.
Don’t pulse and glide; it really wastes fuel. Hybrid owners do this to game the electric engine. Instead, keep your foot on the accelerator just enough to maintain speed. Also, do not turn your engine off while coasting. If you are coasting while your car is in gear, you are using almost no gasoline. If you turn your car off while coasting, expect to cut the life of your starter, igniter, alternator, and transmission in half. Japanese hybrids either don’t have or have modified versions of these components for a very good reason. Last, don’t accelerate at a turtle’s pace, you are preventing the car from getting to the right air-to-fuel ratio it needs for the engine to operate efficiently.
If you don’t believe me, buy a hybrid and test these strategies out. The numbers won’t lie.
@Phoenix –
We’re getting away from hypermiling and into traffic flow, but… It is normal for people to slow down as the number of cars on a road increases. Essentially, there is an inverse relationship between the maximum sustainable speed for a road and the number of cars that are on that road. Those trying to drive faster than that speed cause the accordian effect of traffic. By accelerating more slowly, increasing the amount of space in front of me, and using that extra space to average out my speed, my goal is really just to find the maximum sustainable speed that current traffic conditions will actually allow. It’s coincidental that by doing so, I also get better gas mileage because I am braking/accelerating less.
Plus, teeej is absolutely correct. Just chill out. When traffic is bad, no one is getting anywhere any faster.
Cheers,
Lots of replies… wow.
Check out this video of Wayne Gerdes, the “hypermiling Guru” in action
http://tinyurl.com/58utjd
I just feel that most drivers keep pumping the gas and break pedals as usual.
I disagree with some of what is written in this article.
Cruise control “works” the gas pedal constantly.
The idea is the pedal should stay as stationary as possible.
Cruise control negates this stationary concept.
Maintaining a consistent speed DOESNT HELP!
Maintaining a consistent pressure on the gas pedal does.
Speed drops uphill are good, increases downhill are good to!
Also, leave your tires as they are. Over inflating is a danger to all of us. Not to mention will wear out your tires quicker, offestting your gas savings by hypermiling.
The PROPER way to hyper mile is;
1)Dont push gas pedal down to far during acceleration. Try to keep the pedal as far as it will need to be once you reach cruising speed. In other words, if the speed you desire is 55mph, then push the pedal down just enough during acceleration to achieve this speed. REMEMBER, if you have to let off the pedal when you reach 55mph, you HAVE WASTED GAS!
2)Judge all stop sign and lights by their distance. Begin “coasting” (letting foot off gas) apx 2 tenths of a mile prior to reaching such stops. Most traffic lights will turn during your coasting, thus saving you more GAS!
3)Keep you max speed around 55 or 65 mph. Its always good to keep the RPMS as low as possible so lower speed in a higher gear works best.
4)Never leave your car ideling when unneeded, ANYWHERE! AVOID DRIVE THRUS, and get a little more excercise by walking into fast food/coffee joints.
5)You should always “speed drop” when going up hill. BE SURE NOT TO APPLY MORE PRESSURE TO THE GAS WHEN THIS DROP UPHILL OCCURS. You want to speed drop uphill.
6)Coast down hill as much as possible. If you cannot coast, maintain the same, even consistant pressure on the gas pedal too. Your speed may increase which is fine going down hill. The EVEN GAS PEDAL PRESSURE IS KEY IN ALL ASPECS OF HYPERMILING!
DONT USE CRUISE CONTROL, IT DEFEATS THE PURPOSE!
I own a 2006 VW Jetta TDI. Bought it when the last round of gas gouging occured, when we hit $3.50/gal back in 2005. I saw today coming, so I sold my Escalade and went with something more sensible. My Jetta gets 42MPG without hypermiling, and I NOW GET 60+ MPG USING THE TECHNIQUES MENTIONED IN MY POST ABOVE!
Give it a try and stay in the right lane folks!
Let the other “rat racers” pass you by.
They will learn their lesson soon enough….
ENJOY THE TRIP!
RPMS as low as possible doesn’t always mean best efficiency, you need to look at where your engine is most efficient and that is usually around 1700-2200 rpm but varies from engine to engine. Example try driving 25 mph in 6th gear, you will get better mileage in 4th gear because your vehicle is more efficient in this RPM range.
Oh and one other thing, the concept that hitting the gas full throttle saves fuel is just plain boulderdash!
While it is true, in old carburator models, GAS/AIR mixture is optimal at full throttle (mostly to avoid bogging while accelarating), with fuel injected systems the air/fuel ratio is mantained very very well by the computer thruought the throttle ranges.
Hitting the gas pedal to the ground burns more fuel in a shorter period of time, making it IMPOSSIBLE to even out your NEEDED acceleration.
The proper approach is to hit the gas pedal “just enough” to reach your desired crusing speed;
1)Dont push gas pedal down to far during acceleration. Try to keep the pedal as far as it will need to be once you reach cruising speed. In other words, if the speed you desire is 55mph, then push the pedal down just enough during acceleration to achieve this speed. REMEMBER, if you have to let off the pedal when you reach 55mph, you HAVE WASTED GAS!
aside from being illegal tailgating is obviously very dangerous. I lock my brakes for tailgators.
I think safe hypermiling techniques are great and they can even be utilized to drive more safely than usual. But I really object to people practicing unsafe techniques like drafting or pulse-and-glide – or turning off the engine! That is dangerous and I don’t think the cost of gas is worth risking people’s lives. When you drive dangerously it is not just your own life at stake.
Forget the hypermiling, for an extra $600 a year I will enjoy the quick acceleration of my 6.3L AMG… You also need to calculate how much money your time is worth. If your commute to work is 5 min extra each way, then by the end of the year you have wasted 42 hours of your life sitting in your car. If you get paid more than $538 per week it doesn’t make fiscal sense to drive like this…
Environment… well selling your 1989 5.7L Chevy Pickup and buying a Prius is worse for the environment than just driving your truck till it dies. More importantly the amount of pollution that goes into the production of a prius makes it anything but green… The lithium for the batteries is mined in either China due to its low cost because of lacking environmental safeguards imposed by the chinese government or Bolivia, where it is then shipped to China where they are made into battery cells, and then finally shipped to Japan to be installed into your new prius. At this point the prius boards a diesel powered ship to travel 5500 miles over the ocean over to the USA. At this point it is unloaded from the ship, loaded onto a truck and shipped via diesel truck to the final dealership. At this point the vehicle has already created literally tons of pollution. Even Toyota admits that the production of its lightweight Prius requires more energy and emits more carbon dioxide than the production of its gas-only models.
So if you really want to save the environment, motorcycles have been getting 70+mpg for many years, even the way over powered ones. A step further, buy yourself a nice bicycle and take advantage of the 26% efficient human body compared to the 35% efficient vehicle. Hypermiling is just a silly game made up by people who are not smart enough to realize they’re not really helping the environment, or saving money in the long run.