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We all know how much better a car performs on a cold and crisp winter's night, don't we? Have you ever asked yourself why? Let's take a closer look at what makes an engine tick. Every modern engine requires four basic ingredients which enable it to operate: fuel, air, ignition and compression.

Without any of the above your car's engine won't move a muscle. In today's high-tech environment all the vital components required to operate an internal combustion engine are controlled by an engine management computer with the aid of various sensors in and around the engine to maintain a close-to-perfect relationship between air/fuel mixture and ignition timing. They take into account many factors which can affect your car's performance.

The kit consists of a 4"-diameter air ducting pipe, blanking-off plate for the original air inlet, a flange to mount in the bottom of the aircleaner box, a black moulded scoop for mounting on the inside of the front spoiler, a plastic bag containing all screws, nuts and bolts and two cab~ties.

The sensors are used to relay feedback to the engine management computer to allow for different altitudes, temperatures and the amount of load your engine is being subjected to. The computer is then able to adjust in a split second the varying fuel and ignition timing requirements to maintain a near-perfect balance for optimum engine performance.

I have already mentioned air as one of the vital ingredients your engine needs. Most cars today are fuel injected. Fuel injection provides a much more precise fuel delivery to each cylinder to ensure optimum engine performance under all conditions.

Fuel-injected cars draw the air in via an airflow sensor which acts as an electronic carburetor. This airflow
sensor not only measures the amount of air the engine needs but also measures the temperature of the air coming in and the computer automatically supplies the correct amount of fuel needed to mix with this incoming air.

Due to the fact that the volume of air being supplied to an engine cannot vary because of the design principles, we must assume that to maintain a balance of air fuel mixture, that same mixture must be increased or decreased to compensate for an engine's needs. Let's look at the relationship between an air molecule and a fuel molecule. It takes one air molecule to mix with one fuel molecule, and the maximum volume of air able to be supplied to the airflow sensor is limited. The temperature of the air being supplied determines the size of the air molecules which is directly proportional to the amount of air molecules able to be squeezed into our limited volume.

Picture the maximum volume of air available for an engine as the size of a cardboard box one square metre in size. You then fill this box with tennis balls to represent the amount of air molecules you can fit in this box at say 30 degrees Celsius. Then picture the same size box filled with golf balls, representing the amount of air molecules you can fit in this box at say, 10 degrees Celsius. Remember that one air molecule needs to mix with one fuel molecule, so at 10 degrees Celsius you are able to supply more mixed air fuel molecules than at 30 degrees Celsius.

The colder the temperature of the incoming air charge, the richer the mixture can be, which in turn supplies more fuel to your engine and your engine is thus able to produce more power.

The standard intake system of most cars today obtains air from a small inlet in the air cleaner box which only enables it to pick up air from the engine bay which is already at an increased temperature. If this temperature is too high for the computer to supply sufficient fuel to maintain a perfect balance, your engine may run too lean, which results in a decrease in performance.

To overcome this problem you would have to find a way of supplying your engine with air as cold as possible to maintain optimum performance under all conditions.

Available for Commodores, mainly VL Turbos, VN or VP 5-litre, is a cold-air intake which is 100mm in diameter and picks up cold air from near the front spoiler or bumper bar. This system allows cold air to be supplied to the airflow sensor at a rate which increases with road speed and is not affected by the xcessive temperatures generated in the engine bay.

This supply of cold air allows your engine to operate with a higher level of performance than standard due to the decreased temperature of the incoming air, even on hot days. Obviously, the benefits will be more substantial on cold winter nights. It's similar to an intercooler at a fraction of the cost.

The kit includes everything needed to convert your relatively asthmatic car to a well breathing machine and consists of a 4"-diameter length of air ducting pipe, a blank-off plate for the original air inlet (to prevent any hot engine bay air entering the intake system), a flange which is mounted in the bottom of the aircleaner box, a black moulded scoop which can be used for mounting underneath the bottom lip of the front spoiler, all screws, nuts and bolts required and a four-page comprehensive instruction guide. These cold-air intake kits can increase the performance of your Commodore by three to eight horsepower without any adjustment to your engine and could provide a very cost-effective horsepower gain with the same or better fuel consumption.

The kit was designed by Jim Meyes, an automotive engineer who found that his Commodore was not performing up to scratch on warm days and so designed this system which he has installed on his daily-driven VL Turbo.