"Facts on Fuel Economy Gadgets"

By Mike Godwin

With the steady increase in gas prices, the ads for gadgets that will increase the MPG of your vehicle flourish. Many are in full color and found in very reputable magazines of every type. Some are laid out in black and white and appear to be an article in the publication. Others are plastered on the front page of the check-out stand tabloids. Do they work? That is always a valid question, and the truth is that for the majority of these products, one is better off putting the money on the counter for gasoline, than for the gadgets that are supposed to save so much fuel.

                Over the years, a good many concepts and ideas about the automobile have been conceived in the racing community. Many times the idea is viewed as cheating by other competitors rather than innovative. Old Barney showed up at the plank half-mile track in the early 1900s with a strange bubble on his hood. "The contraption looked like a dog gone scoop for grain turned upside down" one reporter wrote. What the competitors didn't see until after the race when the leather straps were released and the hood carefully lifted clear of the race car was that the scoop had an internal piece that fed air directly into the horn of the carburetor. Born that day was the ram air system.  Did it work? Absolutely!  And it was a feature on many of the high performance cars of the 1960's and 1970's era.

                Simply stated; more air results in better combustion, and better combustion nets two verifiable results.  First - an increase in horsepower.  Second - better fuel economy.  Both gain a result of nearly all of the fuel being burned. Early 289 engines equipped with the four-barrel carburetor showed gains of nearly 5 horsepower when fitted with the optional open element air filter. So a little more air increases MPG for an engine - that is a scientific and measurable fact.  Knowing this little piece of information, the not so honorable producers of several gadgets advertise their product as if it was a new discovery. One item that bolts into the air intake path has "Cyclonic Technology" that causes the air to swirl and as a result, increases gas mileage by as much as 30%. Then in small print, "results may vary" is clearly stated. Not sure what "Cyclonic Technology" is all about, but swirling the air is not going to result in an increase in gas mileage.

                Another of the wonder products boasts about cold air water induction. Actually misting the air with water can help fuel economy when the amount of water injected is closely controlled. As the "Easy to Install" water injection system does not have any electrical connection, the control appears to rely on engine vacuum. Not a very good plan at all as the engine has the greatest vacuum at idle and the vacuum decreases as RPMs increase. So the siphon action that would produce the greatest amount of water in the inducted air occurs when we least desire water in the induction system. Water induction actually does work and especially at higher RPMs, such as those experienced in drag racing. Denser air results in a more complete burn and is the reason you will find many racers using a barometer as a tool to help determine induction setup changes.

                Next is a series of electronic items that are best left sitting on the shelf of the local store or at the mail order house. The one that caught my eye was the system that claimed to boost the output of the coil by thousands of volts. It appeared to connect between the coil and the primary wire of the distributor cap. This item must have been introduced many years ago and the owner is still trying to offload them as most cars manufactured in the past 10 years have stopped using the typical coil and primary wire method of delivering spark to the engine. The claim is based on fact that a higher voltage will produce a better spark and better spark makes for a cleaner burning and more efficient engine. That is where the fact ends for this product, as adding such a device to the modern electronically controlled engine can cause real problems. The new engines rely on numerous signals and temperature readings from various systems including the ambient temperature. Owners also need to keep in mind that the newer cars are equipped with onboard systems called Spark Control Modules. These modules are part of an elaborate interconnected series of modules that control various engine functions. Adding a high voltage module to the system might adversely affect another system. The result is a poor running engine that uses more fuel than before the gas-saving device was installed.

                Another electronic unit claimed to produce great increases in gas mileage by reprogramming you car's computer. Although most of the cars on the road today do have a plug in type access port for diagnostic work reprogramming the system is a bit more complex than a $299 black box can perform. First of all, the majority of the chips in the onboard systems cannot be reprogrammed. So step one is installing a new chip and then installing a new program onto that chip. Most custom speed shops do this type of work with the car on a dyno and present the customer with before and after test results. This type of work is normally done for performance reasons and not to increase fuel economy.

                A couple of things that do work and work very well also deserve to be mentioned. The first is truly easy and is manufactured by K&N Filters. This firm has a wide range of air filters that never need to be changed, and only cleaned occasionally using a special K&N cleaner and oil. The same firm offers a replacement filter and air induction tubes for many cars. These cone shaped filters have been proven to increase horsepower and fuel economy. Remember that the 65 289 cars performed better with an open element style filter.  These new filters are essentially the same thing, just shaped differently.  And best of all, this manufacturer has taken the time to build the entire system to custom fit your Mustang. These filters are easy to install and it is easy to return the car to bone stock if required.

                Another proven manufacturer is the Edlebrock Corporation, which offers a line of cams or kits that contain cams and induction systems, which will improve fuel economy. This firm has several kits for the RV or tow vehicle owner.  There is nothing better than being able to get to the racetrack and have enough money left to get home. Installation of these kits is complex and many times is best accomplished with the engine removed from the vehicle.

                Now for one of the best fuel savers of all time – go easy with the right foot! I have proof of this one with my own car. Having owned the car for nearly 20 years and knowing the gas mileage to consistently be around 14.5 - that is the MPG I use when calculating fuel cost for various trips that I have taken the car on. So last year when fellow MNW member Lori Matthews volunteered to not only drive my Mustang to the MCA show in Concord CA, but to enter the car in the show, I jumped at the opportunity. I calculated the trip at 1,700 miles and calculated the cost of fuel for the trip based on my time proven MPG average. Lori's driving style is much different than mine and she delivered positive proof that her lighter right foot would yield the unheard of mileage average of 18.76 MPG for the trip. Run those numbers and you will discover a 27-gallon difference in the amount of fuel for this single trip. That is a substantial savings, and there is zero investment required. No jackrabbit starts that allow one to zip down the freeway on ramp and no zipping past the guy that is only 2 MPH below the speed limit but on the upside a 4 MPG improvement in the MPG rating for a car is hard to argue with.

Hey Lori (nickname Feather Foot) my next long distance adventure is Phoenix in October.  Any chance that you can teach me your method of easing up on the accelerator between now and then?