One of the most common threads running across all classes of motor racing is that we all need fuel. It does not matter if the fuel is gasoline purchased from the corner gas station, gasoline developed for racing engines, or even alcohol-fuel is a common thread.

As racers, we need to be careful about how we get our fuel to the track. We must remember that we are dealing with a very energy-rich substance. Gasoline and alcohol are, first and foremost, fuels. As such, we need to exercise a respectful amount of care when handling and storing these fuels.

The first thing we need to do is transport fuel only in containers that were designed to carry it, and it should be kept in a well-ventilated area. If you store your fuel containers in your trailer, you need to make sure there is enough airflow even when at rest so there is not a build-up of vapors. If all you smell is gasoline when you enter your trailer, it may be time to look into installing some vents. Don't turn it into a combustion chamber.

Just as you spend money on safety equipment such as helmets and harnesses, you need to think about safety equipment for fire prevention. You should have at least two easily accessible fire extinguishers in your trailer, and it is also a good idea to have a fire extinguisher readily available in your pit spot.

For the purposes of this discourse, we really need to concentrate on the "hows" more than the "whats" involved with fuel. If there is a demand, I will be more than happy to develop a full-blown story about the manufacture of racing gasoline, the role and the specific chemical nature of fuel, how it is blended and manufactured for racing applications, and why these requirements are different from highway gasoline. For now, the more important issues are not the chemistry that makes up the fuel, but the development of the processes and methods we apply to select the fuel we use. After selecting a fuel, we need to understand the correct way to store, transport, and handle it.

There is not a class in racing, at least none that I am aware of, that does not have some very specific rules that surround the fuels used to power its vehicles. Even Top Fuel drag racing has specific rules for the content and make of the fuel used in those engines. The classes at the local dirt track may have a spec fuel that you have to run, which makes the selection process easy for the racer. If you are in a class that is designed around gasoline and the fuel used must be gasoline, the selection processes are a bit more difficult.

The term gasoline is a very generic term that the rule makers intended to be very specific. There is a plethora of fuels that can be classified as gasoline. For example, the fuel used in F1 racing is called gasoline, but try to buy some. It would be easier to get a date with Jessica Simpson for next Saturday night than to purchase 20 gallons of gasoline that the Ferrari F1 team uses.

As local racers, we need to be more concerned with the type of fuel we need rather than the type of fuel we think we need or want. If you are racing in a Hobby Stock or a Bomber class and using a slightly modified or very stock engine, buying a special racing fuel would be a waste of your money. In fact, it might even slow down the car. If the engine you are running has a compression ratio that is less than 10:1, the gas available at the local corner gas station will be more than adequate. There is no need to spend nearly double on racing gasoline.

For the purposes of illustration, let's say that you race in a Hobby Stock class at the local dirt track. Your race car has an engine that has its origin in a mid- to late-'70s pickup. The rules disallow aluminum intake manifolds, so that means you are using a stock cast-iron four-barrel intake manifold. Instead of using the good performance iron heads available, you have some truck heads. No port work is allowed, and you have to use flat-top pistons. You have installed a more aggressive camshaft and upgraded the ignition. You are not allowed to use headers, so you are using the stock cast-iron exhaust manifolds. The remainder of the exhaust system is routed into a collector that exits on the left side of the car. You may have milled the heads, but the compression ratio is still less than 9:1

Given those parameters, what kind of gas do you need to use? Based on the formula described, which is for a textbook entry-level racer, using pump gas from the local station on the way to the track will be more than sufficient for that engine combination. This engine is not a candidate for racing fuel. Save your money and spend the difference on tires.

If the engine in your car has a compression ratio greater than 11:1 and routinely sees sustained rpm levels over 6,000, you have a candidate for racing fuel. If you have an engine that was assembled by a professional engine builder, you should be using the fuel that the engine builder recommends. The real issue with the use of racing fuel, aside from the needs of a high-compression engine, is the elimination of the variation seen in gasoline purchased from the corner gas station, such as octane levels, specific gravity, and vapor pressure.

For those of you who use alcohol for fuel, the difficulties you face are based on series or class rules. When I use the term alcohol, I am talking about methanol. The issues with alcohol are related to storage methods and the impact the fuel has on the engine, fuel systems, and fuel system components from a corrosion perspective. Alcohol is hygroscopic, which means that it will absorb water from the air. The containers used to store alcohol need to be kept air tight. The entire fuel system needs to be serviced on a more frequent schedule than a car powered with gasoline. Many rubbers and metals within the fuel system require more frequent replacement due to alcohol's hygroscopic nature.

There are different grades of alcohol available. You can get methanol that is pure and has a water content of less than 1 percent. While this may not sound like a significant percentage, remember that the alcohol you get at the track may have been exposed to the air longer and is more likely to become contaminated than alcohol that has a guarantee of purity. This level of purity is very expensive because a great deal of care has been taken. You may not even be able to tell the difference in how your car runs.

The transportation and transfer of fuels is something that many racers give little thought. The containers used to transport any gasoline need to be UV proof. The ultraviolet rays in sunlight can break down gasoline. In fact, some racing gasolines can undergo very serious degradation when exposed to sunlight. The container should be either metal or plastic and designed for the transportation of gasoline. If the container is plastic, then one of the best colors to use is black. If you can see the level of the fuel in the container, it is too translucent. Alcohol fuels are not as sensitive to sunlight exposure. Just keep the lids closed to minimize any exposure to the air. This is even more critical in humid conditions.

Another thing you need to remember is the hissing you hear each time you open a can of gasoline is the sound of all the light components of the gas escaping into the atmosphere. You want those light components. Granted, you will not be able to eliminate the escape of some of the light components when you open a container, but there are ways to minimize the escape, so open the can as little as possible. Do not let the fuel can sit in direct sunlight; keep containers in the shade or throw a towel or tarp over them. I have seen plastic cans swell up like balloons after sitting in the sun for a couple of hours. Remember, sunlight is an enemy of gasoline, so do your best to keep the gas cans out of it. This is something you can do to improve quality and reduce the variation in your fuel for free. There's not much you can do in racing that is free of charge and improves performance.

The reality for the Saturday night racer is that there are no pit stops, so fueling the car does not have to be accomplished in 12.5 seconds under the pressure of the race. We have some time to make it happen.

The trick is to keep the fuel clean as it is transferred to the tank. This involves several steps. First, make sure the can is clean prior to putting in any fuel. This includes the inside and the outside of the container. If the outside of the can is dirty, there is always a chance of the dirt or debris falling off the can and into the funnel or the tank. Use a good-sized funnel that is equipped with a filter. You can get some great disposable filters at any automotive paint supplier that are cheap and fit well into the oversized funnel you should be using to fuel your car.

For any of you considering the use of aero gasoline or aviation gasoline, this is fuel designed for use in a piston-powered aircraft, so please just forget about it. It is illegal to pump this fuel into anything that is not an airplane, and the fines are quite high. Aviation fuel was designed for engines that run very low rpm, and most race engines idle faster than airplane engines run at cruise speeds. The chemical makeup is also wrong for the type of engines we use in race cars, so aviation fuel is not even a consideration. It will cause more trouble and there is no upshot to using aviation gas.

Remember, keep the fuel clean, keep it in the shade, and don't spend more for it than you need to. It is just that simple.

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