Thursday, May 08, 2008

Your Car Should Get Better Gas Mileage!

by Michael D Cooper

I don't think of myself as a conspiracy theorist, but sometimes I feel like I may behave as one. The reason is that if you get me on the topic of the automotive industry and the fuel efficiency of cars I'll rant for hours (usually until I've cleared the room). OK, I'm not quite that bad anymore-I can gauge the boredom factor of my audience, but I'll tell you one thing for sure. As gas prices start to approach $4/gallon, people aren't dismissing me quite so quickly anymore.
So how's my rant go?
Well the first thing I like to bring up is that cars today really don't get very good gas mileage when compared to the mileage that cars have gotten over the years. Sure we look at the hybrids and we are impressed that they can get over 50MPG, but honestly, that's no great feat. The 1984 Honda Civic Coupe got 64MPG on the highway and 48 in the city. There's no hybrid out there today that can match those numbers-not even the current Honda Civic Hybrid!
The modern Civic Hybrid doesn't get the same mileage for one really simple reason. It's heavier. Much of that extra weight is from all of the creature comforts that we have come to appreciate in our cars (and that massive rechargeable battery in the car's belly). Most people would be surprised to know that modern cars typically outweigh the bulky steel beasts from the 60s and 70s. The 1968 Dodge Charger (the Duke's of Hazard's General Lee) is outweighed by a Toyota Camry by several hundred pounds.
I tell you this because it is necessary to refute one of the most common arguments that I hear against our car's getting better gas mileage: "If the manufacturer's could get better mileage out of our cars, they would."
That is total bunk
If you look at the average MPG of production vehicles in the USA, it hovers around exactly what the government requires those averages to be. When the government raises the CAFÉ requirements, the manufacturers make their cars get more miles per gallon. Sure they complain about it the whole way, because we've all gotten used to having passable fuel economy and all of the bells and whistles too. Now they have to work out a way to give us both. And they can.
Keep in mind that that 1984 Honda civic that got 64 MPG on the highway didn't have fuel injection; it had no computer to regulate its systems - it used a carburetor (essentially a device with tubes shaped like hour glasses) to mix the air and the fuel.
Back in the 60's though the cars weighed about the same, engines were much, much larger. It wasn't unusual at all to have 5.0 liter and larger engines, even over 7.0 liter engines in cars. Many of these engines achieved MPG ratings into the high 20s and low 30s on the highway. I have owned several cars from the late 60s and early 70s that achieved average city MPG ratings of 22MPG with 5.0 Liter engines.

One of the reasons that this is possible is something called compression ratio. One of the things an engine does when it burns gas or diesel is it compresses the air-fuel mixture before it is ignited. The more you compress the mixture the, the more power you get from the ignition. In the late 60s many cars had compression ratios over 11 to 1 (some as high as 13 to 1). Modern cars have compression ratios hovering around 9 to 1. That means that modern engines have as much as a 30% decrease in their compression and the power they can get from the burning of their fuel (depending on a few other factors as well).
Why on earth is the compression ratio so much lower?
I'm certain that this is what you are asking. The reason is both simple and complex. It is the octane rating of the fuel the car burns. When you look at the gas at the pump and you see those numbers on the regular, mid-grade, and premium blends of gas you may not know what they mean, but those are the octane ratings. 87 through 93, typically-depending on altitude. The higher the octane rating, the more you can compress the air-fuel mixture. In 1966, premium gas had an octane rating of 107. That is what allowed engines to compress the mixture so much more.
It's very important to note that a higher compression ratio causes the engine to have a more complete burn (the molecules are closer together and ignite faster) and reduces emissions. High compression ratio = lower emissions = more environmentally friendly.
The next obvious question is why is the octane level so much lower now? That has two reasons. The first is that one of the things that was used to boost octane was lead. We all know that lead is bad and that burning it in your engine makes for a rather unpleasant exhaust. The second is that the petroleum companies determined that the sweet spot for them to get the greatest yield out of their refining processes was to make 87 octane fuel.
If you don't think that the oil companies and refineries do not work in very close concert with the auto manufacturers, you need to think again. If you had a product that had one, very large marketplace, would you not work very closely with the companies that create that marketplace to make sure that your products work well together? And would you not be surprised if mutually beneficial arrangements were reached that did not necessarily benefit the consumer?
If the auto manufacturers were really concerned about MPG rating, and if they were really concerned about the environment, they would have continued making higher compression engines and the petroleum companies would have been the ones forced to modify their product. What actually happened was that the auto manufacturers dropped the compression ratios on their engines and the petroleum companies got to get more bang for their buck and we all burn more gas on less efficient engines. It's a win/win for them and a lose/lose for us.
We know leaded gas is out - but is there anything else?
If you load the Wikipedia article on octane ratings for gasoline you will find a section that lists the octane ratings for different fuels. You'll note that E85 and Methanol can have ratings in the 105-107 range. That's huge. That means that if an engine was made to burn those fuels specifically the compression could be increased and the power and mileage would increase and emissions would decrease.
Unfortunately the so-called 'flex-fuel' cars that are made that can run on E85 and (rarely) methanol still use lower compression ratios and don't get a really significant benefit. A lot like the time you tried premium in your car and saw zero improvement over regular.
So what can we do?
If you haven't gotten this impression yet, let me re-enforce it. The auto manufacturers are only going to go as far as they have to to meet the requirements that the government sets. They will go no further. It's up to us, the public, to take control of our own fates and expect life changing and ground-breaking things from big business and the government.
Just a few short years ago the Ansari X-Prize was announced. 10 Million dollars for the first private company to get a ship into space twice within 2 weeks. Many companies entered with varying degrees of success and many naysayers said it couldn't be done-that only projects with massive funding from the government could get people into space.
Scaled Composites, a US company expended (at my last time of reading) roughly $20 million dollars and got a man into space. The current X-Prize is going to be awarded to the first non-government agency to build a car that can get 100MPG and then win a race against other entrants. The cars have to have things like air conditioning and stereo systems. Already private entrants (often part time hobbyists) are producing prototypes that are getting over 90MPG - from vehicles they are building in their garages.
Just like when the automotive revolution began a century ago, it is the everyday Americans and inventive people from around the world that are stepping up and trying new and exciting things to solve problems that big business and the governments are stymied by.
Get in on the exciting changes.
There are a lot of things you can do and try. From altering your car to burn E85/Methanol (and even if you only get moderate MPG improvement - helping the environment), to burning vegetable oil in your diesel (commonly known as biodiesel), to revolutionary water electrolyzers that extract HHO gas from water and burn it in your engine.

Check out alternativefuelupdate.com to learn about many of these exiting ideas, solutions and products that you can take advantage of to join the revolution and (if you'll forgive my slightly conspiracy theorist sounding term) stick it to the man.
Michael Cooper is an automotive enthusiast and he has been working on cars since he was 8. Visit his new site http://alternativefuelsupdate.com to see the products and technologies he recommends to get better gas mileage.

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