The Real Way To High Gas Mileage
November 1, 2009
By Scott Lewis
Many people believed, or still believe, that the car manufacturers don't build cars that get 50, 60 or even 100 mpg because of some conspiracy by the oil companies. I think after a bankrupt Chrysler and GM we can put that conspiracy to rest. If it were possible to build such a car surely one of the car makers would have done it by now to bury all the competition. I mean really, who goes into bankruptcy while getting there pockets lined by Exxon/Mobil.
There is no magic 100 mpg car out there. But what would it take to
build a car that got 50, 60 or even 100 mpg? Now we have something
realistic to talk about. It is not that the technology does not exist to
get 50+ mpg, it's just the cost of
It is true that cars are not getting much better mileage now than they did just 10-15 years ago. My 1993 Camaro with a V-8 was rated at 23 mpg on the highway. The new Camaro equipped with a V-8 is rated at 24 mpg. Wow, a 1 mpg improvement in 16 years.
Let's go back even further. When I had my 67 Camaro RS Convertible it too had a V-8 engine and I got about 19 mpg overall. I regularly got 19-20 mpg with my 93 Camaro. I drove a 2010 Camaro in New York for a few days and averaged just over 20 mpg... with the V-6, not the V-8.
So why has the Camaro's overall mileage not changed much
in 40 years?Let's break it down like this:
Year Engine HP Weight Performance
1967 327 V-8 210 3200 lbs. 0-60 approx. 9 sec.
1993 350 V-8 275 3500 lbs. 0-60 approx. 5.7 sec.
2010 376 V-8 426 3900 lbs. 0-60 est. 4.7 sec.
Do we see a trend here? Granted all the numbers above are approximations, but they do tell the story. The Camaro has gotten heavier; with bigger, more powerful engines; and faster. All the while maintaining gas mileage for over 40 years. It is not that Chevrolet can not build a Camaro that gets 40-50 mpg. It's just that people don't want a Camaro that is as slow as (or slower) than a base 67 Camaro of years gone by.
Maybe you think a sports cars is unfair. O.K. Let's look at one of the most popular sedans sold in this country, the Honda Accord. Here is a basic list of changes the Accord went through since its introduction in this country in 1976:
1976 - 1.6 liter I4 with 68 horsepower. Approximately 2,000 lbs.
1979 - Engine grows to 1.8 liters, output to 72 horsepower.
1984 - output increases to 86 hp.
1985 - Fuel injection adds 24 hp to 110 hp. Weight hits 2,341 lbs.
1986 - Weight grows to 2,529 lbs., engine to 2.0 liters.
1990 - Weight up to just under 3,000 lbs. Engine up to 2.2 liters/130 hp.
1995 - Enter the V-6 at 2.7 liter with 170 hp.
1998 - Redesigned with a 3.0-liter V6 producing 200 hp.
2003 - More power and size, 3.0-liter V6 pumping out 240 hp.
2009 - Yep. Power is up with a 3.5 liter V6/271 hp. Weight hits 3,567 lbs.
People don't want small, slow cars. So the cars get bigger and faster and mileage increases slightly because the real demand is for performance and size not mileage.
The 09 Accord is now classified as a large sedan, up from mid-sized. This V-6 Accord is rated at 19 mpg city and 29 mpg on the highway. Honda's 4 cylinder Accords are only rated 1 mpg better on the highway than the V6. If Honda put its R&D into light weight materials over the last 30 years we would probably have a nice 2,500 lbs. sedan that got 50 mpg but was only good for 0-60 times in the 9-10 second range. Oh the shame of it all.
What would have happened if Honda spent the last 3 decades only
improving the mileage of the car. Hmm! The Mini Cooper weighs just over
2,500 lbs. and comes with a 1.6 liter engine with 118 hp that gets 37
mpg on the highway. If we shave 500 lbs off the Mini Cooper and boost
mileage at the cost of performance we could easily break 40 mpg. How
much would it take to hit 50... if we were really trying.
The government does not want cars that get good gas mileage. Oh sure, the feds are pressuring the manufacturers to build higher mileage cars. Yet year after year they force new restrictions on those auto makers. Restrictions that directly go against gas mileage.
Emissions standards keep getting tougher, and the feds do nothing about stopping states from implementing their own standards. It is expensive for all auto makers to meet different standards in different countries, no less in different states. With the R&D used on ever tightening & different emissions standards R&D for mileage has to take a back seat.
Adding more and more emissions to a car hurts performance and mileage. Since we have to get back that lost performance mileage takes a double hit as the emissions regulations get tougher. I am not saying we don't need emissions equipment on cars, but could we set one standard that every car must meet... and keep that same standard in place for a decade or so. Give the manufactures (all of them, not just GM & Chrysler) a chance to work on mileage instead of emissions.
We also have safety equipment. Many safety features add weight to a car. Structural beams add weight. Air bags and their electronics add weight. The electronics and sensors and such for traction control adds weight. Plus these things cost money. Money that must go toward developing them instead of putting the research into improving gas mileage.
Cars are leaps and bounds safer & cleaner today then they were 20 or 30 years ago. How about leaving the safety and emissions standards alone for a while. If a manufacturer wants to develop a safer system and charge extra for it on premium cars, let them. Don't make them put that technology into all cars. If you have to add a $900 traction control device to a $15,000 car then where is the incentive to add another $900 for the Direct Injection version of an engine in that same low cost vehicle.
Would the buying of an economy car want traction control or 3 mpg netter mileage if they had to choose which one came on a car (assuming each of those cost the same)?
How To Achieve 50+ MPG
Let's take a look at some of the technology to improve mileage that has been introduced over the last few decades.
We had carburetors in the 60s. We went to electronically controlled carbs in the 70s. The 80s saw throttle body fuel inject, which is really just a better electronically controlled carb using solenoid injectors instead of float bowls and venturies. Next up was multi-point fuel injection where the fuel is injected into the manifold close to the cylinder head (making the intake manifold a dry flow system). Finally we come to Direct Injection where the fuel is injected directly into the combustion chamber (like on diesels). Each advancement gives more precise control over fuel to get me most out of it.
What about turbocharging. When turbocharger started to become popular in the late 70's they talked about using smaller turbocharged engines as replacement for larger engine. The idea was to get the best of both worlds... good performance and better fuel economy. Certainly we have proven over the years that we get better performance. My own BMW 335i has a twin turbo 300 hp engine that will move the car to 60 in a tick or two over 5 seconds. But my Bimmer only gets 27 mpg on the highway (according to the EPA). I managed 31.7 on a recent trip to Fort Worth, but that is a story for hypermiling).
Turbo charging an engine is not cheap. There are some real costs in parts, and R&D to add turbocharging to an engine. How many people are going to pay for 335i performance to get 328i performance, but with a 3 mpg better economy. The expense of turbocharging has always been left for performance cars. In economy cars it has never panned out. Even when it worked... such as for Fords Mustang SVO. You got the same performance as the V-8 Mustang, but got better mileage and better handling as a bonus. But it did not sell. Because people liked the cheap performance and did not care about the mileage. But for this article we can change that... and put the cost toward mileage.
We have roller camshafts to reduce friction in the engines. We have synthetic oils that work better at reducing friction that traditional oils. 3, 4 and 5 valves per cylinder over 2. Double overhead cams (DOHC) instead of a single cam in the block or even single overhead cams. Variable valve timing. Electron control management. Etc, etc. These things add up. Aluminum engines are lighter that iron engines which help with overall weight of the vehicle.
Transmissions have gone from 2 speed, to 3 speed, to 4 speed, to 5 speed and even 6 and 7 speeds. Each gear addition allows the engine to operate in a more ideal rpm range to move the car better while improving mileage and performance. We could skip the performance gain and focus this on better mileage.
Carbon fiber body panels are very expensive, but they reduce weight. Aluminum saves weight over steel. Take a look at the Lotus Elise. This cars weighs less than 2,000 lbs. 1,984 to be exact. This car has a 189 hp engine that delivers 0-60 times of 4.9 seconds while getting 27 mpg on the highway. What if we cut the hp back to 100 and had a target performance of 0-60 in 9 seconds. I'll bet we could hit 50 mpg. Don't get me started on the Tesla, which is essential a Lotus Elise with an electric drive train and batteries. Yet people think spending over $50,000 more than the Elise is a good idea. I hope these people don't expect us to believe they are going to save $50K in gas over the life of the car. It's not going to happen. But it does show us what can be done with a lot of money.
The Elise/Tesla is an extremely small car, so it is not practical as a family car. But if we used the same techniques to build a family car we could build a reasonably sized sedan that weighs about 2,500 lbs. It would cost upwards of $100,000 with a small gas engine or maybe close to $150,000 for an electric version that was practical (had the range to make it usable for daily driving).
How many people will step up and pay over $100,000 for a sedan that gets 50+ mpg. More important is how many people are going to pay for this instead for paying for luxury and performance.
The Chevrolet Yukon Hybrid had to go on a diet. Adding the hybrid components and batteries to this vehicle added 500 lbs., so they had to find ways to reduce the weight. They used plenty of lightweight, and expensive, materials to shed that 500 lbs. What mileage would the Yukon get with just the 500 lbs. savings? We will never know, but they could have put in a smaller V-8 engine and got the same performance because of the lighter weight. Would this been as much a benefit as the hybrid. It would not be sexy like a hybrid is, but what if it gave the same results. It would prove our point that all you really have to do to get better mileage is to focus on mileage... and pay for it. But nobody will pay for it.
How NOT To Get 50+ MPG
On the flip side, I was as a car show this past weekend and there was a brand new Ford Taurus SHO parked next to a 67 Pontiac GTO. The GTO looked tiny next to the Taurus. I looked it up and the Taurus has grown to 4,368 lbs. That's SUV territory. No wonder we don't have family cars that get 60-70 mpg with our lust for such big, heavy cars.
Any weight savings we might get from expensive alloys is wasted by adding comfort and convenience items or government mandated safety features. Air bags, side impact beams, traction control, stability control, air conditioning (front and rear in some cars and SUVs), power windows, power locks, CD changers, GPS navigations systems, Bluetooth modules, iPod integration, DVD Entertainment systems with multiple screens, iDrive control systems, rear parking sensors and/or cameras, heated and cooled seats, radar enhanced cruise control, lane departure systems, etc., etc. etc.
How about those 20 inch wheels like on the new 2010 Camaro. Those add weight to the car, and it is also unsprung weight that hinders handling. Plus the increase in rolling resistance that must be overcome to get to and maintain highway speed. Ouch!
All this adds up to cars that don't get better gas
Well, I think it is obvious that any conspiracy is in plain view... the government can push the auto makers around and push them into and out of Bankruptcy Court. Heaven forbid they just stop adding the burden of tighter emissions and more safety requirements. Cars are safe and clean enough that we should leave that alone. Can't we take a 5 or 10 year break from safety and emissions and use that time toward concentrating on getting better gas mileage?
If the government wants to clean the air they should expand the cash for clunker program to get rid of as many old cars still spewing large amounts of pollution as possible. Heck, why don't they put stricter emissions on factories that spew all kinds of crap into the air.
If they want cars to be safer make it mandatory for the driver to take an advanced driving course that really teaches people how to drive safer, rather than make the cars idiot proof. How about educating people to be safer drivers instead of burdening the manufacturers with every increasing safety standards.
So, you want a car that gets 70-100 MPG. Simple. Expect to spend around $150,000 for a super lightweight car with a super efficient engine designed for mileage, not performance. If K-Cars could get 37 mpg in the eighties, we should be able to double that today... as long as you are willing to live with K-Car performance today.