2009-07-31

Best In Class Gas Sippers of 2007


If you are thinking of getting a new car and want to save on gas at the same time, you might want to think about buying a used car. After a couple of years, the sticker shock price on cars comes down, so buying a 2007 model can save quite a bit of money. At the same time, you have a car that is almost new. When looking over what is available for the 2007 model year, you might like to know what is the most fuel efficient vehicle in each class. Here is the official EPA list.

For each major class of vehicle, this table gives the make and model (for the 2007 model year) that gets the best gas mileage. It also includes the city and highway mileage estimates for that model.

2007 Model Year Best-In-Class Fuel Mileage
ClassMake/ModelCity/Highway
Two-SeaterMazda MX-5 (manual)25/30
Minicompact CarNew Beetle Convertible22/30
Subcompact CarToyota Yaris (manual)34/40
Compact CarHonda Civic Hybrid49/51
Midsize CarToyota Prius (hybrid)60/51
Large CarHyundai Sonata (manual)24/34
Small Station WagonHonda Fit33/38
Midsize Station WagonFord Focus Wagon (manual)27/37
Sport Utility VehicleFord Escape Hybrid FWD36/31
MinivanDodge Caravan 2WD20/26
Pickup TruckFord Ranger Pickup 2WD (manual)24/29
Mazda B2300 2WD (manual)24/29
Van (Cargo&Passenger)Chevrolet G1500/2500 Chevy Van 2WD15/20
GMC G1500/2500 Savana 2WD Cargo15/20

2009-07-30

EPA Fuel Economy Labels


Cars sold in the US are required to display a fuel economy window sticker. This allows consumers to see the estimated mileage per gallon the vehicle gets in both city and highway driving. Consumers can use the information to compare different vehicles. Starting with model year 2008 the format of this information as well as the tests used to derive it have changed. The changes are in response to consumer demand for better information. In particular, the newer tests account for faster driving speeds and greater acceleration. They also take into account usage of the air conditioner and colder outside temperatures.

Looking at the label itself, you can see the two estimates for city and highway driving on the two sides. In the center is the cost of gassing up the vehicle for a year, based on an estimated price of gas and driving distance. Your numbers will be different, especially the cost number. It is hard to get mileage much better or worse than the estimates, but it is easy to drive much more or less than the estimated distance. Also in the middle, below the annual cost of gas estimate, is a bar with a triangle pointing to an overall mileage combining city and highway values. It shows on the left and right ends the range of MPG values for vehicles in the same class, for example SUVs or light trucks. This lets the consumer see how the vehicle stacks up against similar choices.

The choice of vehicle has a big potential to allow you to save on gas. Don't ignore potentially helpful information on the fuel economy labels!

2009-07-29

Fuel Economy Triad


All of the factors that govern your car's gas mileage can be broken down into three groups. Your choice of the make and model of car you drive, how you drive and the mechanical condition of your car make up the Fuel Economy Triad. Think of them like the three legs of a stool: all are necessary to support the load. Depending on your individual situation, one or another might be easier to manage, or potentially give a bigger savings on gas. But you should always keep all three in mind.

An example of the driving habits leg is reducing the number of small trips you make. If you are in the habit of driving a couple of blocks to pick up a pack of smokes, then walk instead. Or make one trip per week to the grocery store and buy twice as much instead of two trips. This is not a practical solution for most of us, but if you can move closer to work or find a job closer to home you can save a lot on gas for the commute.

The make and model of car you drive sets your base fuel economy. If you drive a vehicle that gets poor gas mileage you are going to be using more gas no matter what else you do. Of course, there are other reasons besides gas mileage for choosing a vehicle and it is not always so easy or practical to change vehicles.

A car that is not mechanically tuned up and cared for will get worse gas mileage. If the tire pressure is not high enough or you have a roofrack you don't use, you will be using more gas than is needed. Get your vehicle checked up regularly and stick to the scheduled replacement times on components like the air filters. You will be rewarded with a savings on gas.

The leg most commonly overlooked by drivers is their own driving habits. Don't make the same mistake: always think about the whole Triad!

2009-07-28

Thinking About Diesel


What are the differences between diesel and gasoline engines? Can these differences help us save on gas? Well, first of all, diesel engines have a higher thermodynamic efficiency. When they burn fuel, they convert a higher percentage of the energy available to useful work. Basically, all else being equal, they get more miles per gallon. However, to get these high efficiencies, they run at very high compression pressures. Because of this they need to be built strong, which makes them heavier. They are also more expensive to manufacture because of the strength requirements. Another feature is that diesels don't need electrical ignition systems, because the compression pressure is enough to cause the ignition. They need complex fuel injection systems though.

One interesting feature of diesels is that they can run on very low quality fuels. Even vegetable oil is enough to run them on. Try that with a gasoline powered car engine!

2009-07-27

Velozeta Six-Stroke Engine



Six stroke engines add another two piston motions to each fuel injection cycle to those of the common four stroke engines. Everyday cars and trucks use four stroke engines. These are called four stroke because for each time that a new shot of fuel is burnt, the pistons sweep up twice and down twice, for a total of 4 sweeps or strokes. The four stroke sequence goes like this:

Intake Stroke
This stroke begins with the piston at the top of the cylinder. The piston moves down, opening up space in the cylinder. As it does so, the valves in the head above open and fuel-air mixture gets sucked into the cylinder.
Compression Stroke
When the piston reaches the bottom of the cylinder, the valves close off. As the piston rises up the cylinder, it compresses the fuel air mixture, which now has nowhere to go. This compression primes the mixture for detonation. The stroke ends with the piston at the top of the cylinder and the mixture compressed into the small space in the head above.
Power Stroke
Now the fuel air mixture is detonated by the spark plug. The resulting explosion forces the piston down the cylinder and rotates the crankshaft against any attached load.
Exhaust Stroke
Exhaust valves in the heads above open up, and the piston rises up the cylinder, forcing out the exhaust gases, which are the ashes resulting from the combustion of the fuel air mixture.


Students from the College of Engineering at Trivandrum in India have developed an engine which adds two more strokes after the exhaust stroke. It uses air to scavenge heat from the cylinder and convert it to motive power. This can improve efficiency, because normally that heat is just wasted. The engine is a modified Honda four-stroke engine. After the exhaust stroke, valves open and allow cool air to flow in as the piston descends. The air gains heat from the very hot cylinder which causes it to expand. This heat-driven expansion occurs forcefully enough to actually power the piston down. In other words, there is a secondary, weaker power stroke after the exhaust stroke. On the sixth stroke (which is a secondary exhaust stroke), the rising piston forces the now warmer air out the exhaust.

This engine uses 40% less fuel and can run on normal gasoline.

2009-07-26

Gas Sipper Extraordinaire: 8,923 MPG


Can you imagine getting 8,923 miles per gallon?! That is enough to go around the entire planet Earth on about 3 gallons! The Microjoule is a French vehicle designed to run on normal gasoline. It was built as an entry in the 1985 Shell Eco-Marathon, which is a contest to see who can build the vehicle that gets the best gas mileage. It is a lightweight single-seater, so no carrying the kids and the groceries. You can see in the picture that it is about the size of a man. Kind of a driving coffin, if you want to look at the bad side of things.

The Microjoule has a reverse tricycle wheelbase. Three wheels with the point of the triangle towards the rear. No alien technology here, the secret to the unbelievable mileage is the clean aerodynamic shape. Three cheers for French technology! Now if only Detroit had half the brains of the French, maybe the US automakers would not be going down the crapper.

2009-07-25

Gasbuddy


In a local area, the price of gas can often be different by up to 20 or 30 cents at different filling stations. If you can find the cheapest one that is not too far away, you can save quite a bit on gas. The problem is how do you keep an eye on all the regional filling stations to know the prices? There is no way that we have time to phone around and ask them all, and if you drive around to see, you will burn a fortune on gas! Fortunately there are websites to help us. One of them is Gasbuddy. Check them out!

2009-07-24

Don't Pay for Octane You Don't Need


The octane rating of a fuel tells how resistant it is to "knocking" or "pinging". This happens when the fuel-air mixture in your cylinders explodes before the spark tries to set it off. Early explosions that are not timed exactly to the piston position can rob power from your car. High compression pressures in the cylinder are the cause of early explosions, or preignition. The compression pressure is something that is designed into your engine. So you can use the lowest octane that does not cause knocking. Higher octanes do not give you better performance, because the compression pressure of your engine is fixed. This can save on gas money quite a bit!

Tip: you can mix gas of two different octane levels to get what you need. Imagine that your car needs at least 87 octane, and anything lower will cause engine knocking. If your service station has 85 and 89 octane, but no 87 octane, then putting in the 89 octane will keep your engine from knocking, but you are paying the higher price. What you can do is buy half a tank of 85 octane, and then top up the other half with 89 octane. They will mix to give you the 87 octane that your car needs, but you only paid the expensive price on half a tank!

2009-07-23

Maybe Skip the Acetone

Yesterday's post talks about the possibilities of adding acetone to your gas to get better gas mileage. Here is a second opinion. According to Bobby Likis in this video, acetone might clean carbon deposits out of your fuel system, improving the gas mileage a little. However, cars are not designed to use it. Acetone might damage the wiring of the fuel pump or the fuel injector system. Also all of the rubber seals in your car could be damaged. Bobby's recommendation: don't put acetone in your car. Watch and see for yourself!

2009-07-22

Acetone for Better Mileage

Some people say that you can get better gas mileage by adding some acetone to your gas. When your car burns fuel, it is actually burning gasoline vapor, not liquid gasoline. If you have ever dropped a match into liquid gasoline, you have seen that the whole thing does not explode. Instead, your car combines gas vapors with oxygen from the air to form an explosive air-fuel mixture. Then a spark from the spark plug detonates this air-fuel mixture, which has enough explosive power to throw the piston up against all the load your car is putting on it.

The idea with acetone is that adding it to gas will make the gas vaporize better, reducing the amount of liquid gasoline droplets that may get into the cylinder helping generate a more complete burn. This will get you extra mileage.

In this video, Dr. vonHypermiler says he uses acetone with no harmful effects on his engine. He puts 2 ounces of pure acetone per 10 gallons of gas and gets savings on gas of 9.64% !

Watch his video and see what you think!

2009-07-21

New Website From the Government



The US Department of Energy and the US Environmental Protection Agency have teamed up to create a great new resource for saving on gas! They have put up a website fueleconomy.gov which has the goal of reducing gas consumption in the US. The website allows you to search for cars and find their gas mileage as well as compare cars side by side on mileage. There is a mileage calculator, and the website allows you to see MPG data put in by other people who have the same make and model vehicle as you. This gives you the ability to see if you are using more or less gas then normal. If you are using more than average, it is probably time to go in for a tuneup, or think about adjusting your driving habits.

There is information on alternative fuels, and a section to help you locate the lowest gas prices. A section talks about diesel as an alternative fuel, and discusses the potential of biodiesel. Biodiesel is diesel fuel derived from plant matter, and not petroleum. There is even a section which explains the Cash for Clunkers program.

This site deserves a good look over, because there could very well be some excellent information for those of us trying to save on gas.

2009-07-20

Think about the Price, not the Brand


Try not to think much about the brand when you fill up your gas tank. Look for the station offering the best value for your money. Remember that gas is a fungible commodity, which is econospeak meaning that gas is a widespread and interchangeable product. It really does not matter which brand you buy or what the logo on the pumping station sign is. All gasoline sold in the US must meet the basic standards set by the government. It is true that each brand might put in their own cocktail of chemical additives, but these additives are also government controlled. In fact, many gas stations will buy their gas from the same refinery no matter what the brand. Smaller cities might have only one refinery close by.

So to save on gas, think about value for your money and not brand loyalty. Remember that the brands are sure not loyal to you, so why should you be loyal to them? While you are thinking about value for your money, remember to include distance to the station. A station with cheap gas that is a distance away might cost you more after taking into account the gas you burn going there and back.

2009-07-19

Piston Rings



The piston rings in your car's engine are what keeps the compression build up in the cylinders. Anything off kilter with them will lead to loss of performance and efficiency in your engine. Here is a little video explaining how they work, and what the difference is between gasoline and diesel engine piston rings.

2009-07-18

Sparkling Clean Spark Plugs



The job of the spark plugs is to ignite the fuel-air mixture inside the cylinders. The resulting explosion forces the piston back up the cylinder, which provides the power to turn the crankshaft. In top shape, the plugs provide just the right amount of electricity to efficiently burn all of the fuel. If they are out of shape, some of the fuel could be going unburnt, or the spark could be setting the explosion off out of timing. Out of timing explosions can work against the crankshaft, robbing power from your car. Both of these things can cost you gas. If your plugs are fouled by oil or just worn out from a long service life, you will be getting lower gas mileage than you should. Simply keeping your plugs like new can give you 4 or 5 miles per gallon more, helping you save on gas. Have your plugs checked or changed every 30,000 miles.

2009-07-17

Right Turn Theory



How many times have you been waiting in busy city traffic to make a left turn? Sometimes you have to wait for 2 or even 3 cycles of the light before it is your turn. Ever thought that maybe you could get where you are going faster if you took a different route, one that only made right turns? City road layouts are often based on square grids, and when you stop to look at it, on square grids you can go between any two points making either right or left turns.

Even if the all rights route is a little longer, you might actually get there in less time. And if you are not sitting idling the engine in line at the left turn light, you will also save on gas.

2009-07-16

5 More Tips to Save on Gas


Drive Green: How To Save Money On Gas

Here are five more tips for how to save on gas. Keep your gas cap tightly fitted so you don't lose gas to evaporation. Keep your air filter clean. Very important one here: keep your tires inflated to the correct pressure. Have tuneups done regularly. The last tip is one that is easy to overlook. When you are doing city driving, keep your gas tank less than half full. Why? To save on weight. Having to haul around the gas in your tank makes your car do extra work, which burns extra fuel. In the city, you always have a filling station close by so there is no need to burn fuel carrying a reserve. Go ahead, watch the video, and save on gas!

2009-07-15

Save on Gas - Drive Blood Car!

The amount of money we spend on gas is not at all funny. Here is a little humor to help take our minds off of the drain on our wallets.

In this movie, the price of gas has gone up to $40 a gallon. Scientists all over the world are scrambling to find alternative fuels, and finally they find one .. human blood! The homepage for the bloodcar movie is here. I haven't seen it, and it looks really bad, so I can't say that I recommend you see it either.

2009-07-14

Truck Beds - Cover Them Up!


At higher speeds, especially at 50 mph and up, aerodynamic drag becomes a big source of friction. Friction that your engine needs to burn fuel to overcome. This costs you by lowering your gas mileage. So, you can save on gas by having a sleeker, more aerodynamic vehicle. There is not much that can be done to lessen the aerodynamic drag on a typical passenger car, but if you have a truck with an open, empty bed, you are wasting gas that you can easily save. Those big, empty truck beds cause a lot of aerodynamic drag at highway speeds. You can drop that drag by 10% putting a cover on your truck bed. Truck owners go ahead and cover up those beds! Save on gas at almost no cost to you!

2009-07-13

Watch Out for Oxygen Sensor Problems


If your car uses an oxygen sensor (all the new ones do), then make sure it is not malfunctioning. The job of the oxygen sensor is to measure how much oxygen there is relative to fuel in the combustion mixture. What can happen is that faulty or old sensors can start to register more oxygen then there actually is. In response, the computer in your car will flood in extra gas to try to get the right fuel/air ratio. All this extra gas is not really needed, and just gets wasted. Result: you can get really big drops in gas mileage. A malfunctioning oxygen sensor can give a 40% drop in miles per gallon. That's right. A big fat 40%. Old sensors can give 20% drops in gas mileage.

If you have noticed that suddenly your car seems to be burning a lot more gas lately and you really don't know why, because you didn't change anything and nothing seems to be wrong, suspect the oxygen sensor. Have your oxygen sensor changed every 30,000 to 60,000 miles. The few bucks to have it done is worth it to save on all that gas!

2009-07-12

Underdrive Pulleys


All of the belt-driven accessories in your car, like the water pump, alternator,and power steering pump, are using up some of the engine's horsepower. An underdrive pulley is designed to reduce the amount of energy going to these accessories, which leaves more for the engine. These pulleys have a smaller diameter than the car’s stock pulley. This means they decrease load on the crankshaft at the price of rotating more slowly. Installing a set of these can increase your gas mileage by 1 or 2 miles per gallon! The next time you think about upgrading or doing some mechanical work on your car, why not add a set of these and save on gas.

2009-07-11

Shed Pounds to Save on Gas


Every pound that your car has to haul around costs you gas to do it. The friction or resistance that your car has to work against generally goes up proportionally to the weight of the car. You can see a similar principle at work down at the drag strip. Drag racers cut away extra weight so they can get better acceleration for a given horsepower. In our case, we want to get better mileage per gallon for a given engine, but the basic idea is the same. For low speed driving, the amount you can improve your gas mileage depends on the weight you shed relative to the weight of your car. If you have a 1000 pound car and shed 50 pounds, that is 5% of the car's weight. In this example you would get up to a 5% increase in mileage.

You can't put your car on a diet, so how to shed those extra pounds? You could replace your rims with light aluminum ones. Replace steel body panels or the hood with a modern, lighter composite material. Throw out all of the junk in the trunk. Don't carry around bags of salt in the summer. If you have a huge toolbox that you never use, consider leaving it at home. This is maybe going over the top, but the fanatics out there could even leave behind the spare tire.

2009-07-10

Interview with a Hypermiler

Wayne Gerdes is a hypermiler, and one of the best. He can get more miles out of a gallon of gas than most people could believe. While his techniques are not all applicable to everyday driving, most of us could learn a tip or two from him about how to save on gas.

Here is an interview with Wayne discussing how to go 1000 miles in a Ford Fusion with only one tank of gas.

2009-07-09

Hypermiling - Gas saving by habit

"Hypermiling" is the art of driving using practices and habits that give extremely good gas mileage. Watch as Sean Symons demonstrates getting 65 miles to the gallon in a hybrid Honda Civic. Notice how when he is slowing down behind the red truck at the lights the engine switches off.

2009-07-08

Prepaid Gas Cards

Sometimes the way you pay can help save on gas. Discounted prepaid gas cards can sometimes get you a 10% savings. These cards are similar to debit cards, but are only good for the purchase of gas. You get one with a preset starting balance. The trick is that gas companies will offer incentives for buying these. Maybe you can get a balance of $55 paying only $50. That 10% savings doesn't look like much on each card, but 10% is 10% and over a year it adds up. Another advantage is that is helps you budget your gas use. If you give yourself one card, you know when it is gone. But if you pay for your gas out of your pocket, it can be difficult to notice where it all goes to.

This guy thinks prepaid cards are a good idea too.

2009-07-07

Update your Driving Habits

I am afraid that high and higher gas prices might be here to stay. The big gas price spike last year is past (thank goodness). Right now we still have $2.50 gas all around us, which is not like it used to be. So maybe it is time to think about our driving habits. We learned to drive in a time when gas prices were low enough that you really didn't think about it much. Now we have to relearn some basic habits so we can save on gas while driving.

How you brake can make a big difference in saving or wasting gas. Cars use more gas speeding up (accelerating) then when cruising at constant speed. When you are cruising steadily, the engine only has to burn enough gasoline to combat friction. But when you speed up, the engine has to both combat friction and generate enough extra power to up the speed. So to get better gas mileage, you have to keep the car going at a smooth, steady pace.

A lot of drivers alternately mash the accelerator pedal and the brake pedal. In a line of traffic, they move up to the car ahead, then brake and fall back. In reality, this is not necessary. Most of the time you can keep your position using only the accelerator. Just open up a little more space between you and the car ahead. Then keep watch not only the car right in front of you, but the action happening up front several cars away. Now you can see slowdowns coming, and instead of hitting the brake, just ease up a bit on the gas. I bet you can get 10% better gas mileage this way.

Try it and leave us a comment here on Save on gas telling how it works out for you!

2009-07-06

Futuristic gas sipper


We all know that one way to save on gas is to drive a car that gets better mileage per gallon. Case in point: the Feds are sure in love with that idea ... they want US automakers to improve fuel efficiency by 40% as soon as 2016. This will be a tough challenge for the automakers. We will see how it all works out. Meanwhile, on the home front, most of us just cannot go out and buy a newer fuel sipper. Unless you are rich, it is just not practical to change cars like you change socks.




Even though for most of us it is not an option, it is fun to see some of the new gas sipping concepts popping up nowadays. Take a look at this one: the 2010 MDI AIRPod. It is powered by compressed air. Although tiny, it holds three people. One person has to sit facing backwards. It can go 130 miles between "fill ups" and has a top speed of 40 mph. It carries an air compressor, so you can just plug it in to any outlet, wait 4 hours, and then you are filled up and good to go.

Here is what the manufacturer MDI has to say about the Airpod.

2009-07-05

Quick fixes can add up

Did you know millions of gallons of gasoline evaporate every year? This can be improved by something as simple as making sure you have a tight fitting gas cap. Tip: replace the gas cap every three or four years.

In this video, mechanic David Rogers shows how a few easy mechanical tune ups can help your car get better gas mileage. Another quick tip he has: make sure your air filters are clean. Filthy filters make your car work harder to get air, which makes it burn more gas per mile. Change the air filter every other oil change. The gas filter also should be clean. Guarantee that it is by replacing it once a year! Last tip for the road: corroded spark plugs will not burn gasoline efficiently, so keep those spark plugs up to snuff too!