performance Article

The Basics Of Performance Engine Upgrades - Part 1 - Intake
By Kevin Schappell

When looking to add power to your engine, it's helpful to think of your engine as a big air pump. Air enters through an air filter then gets mixed with fuel in the carburetor. Once ignited in the combustion chamber it exits through the exhaust system. As with any fluid, air can be restricted and efficiency suffers do to restrictive air filters, cylinder heads and exhaust systems.

Removing this restriction is the goal in gaining more horsepower from your engine. It's easiest and cheapest to work on either end of the system. Intake and exhaust system upgrades are among the most popular and effective changes you can make to an engine.

Today we are going to talk about the intake system. The main purpose of the intake system is to deliver filtered air to the carburetor. Filtration is critical to long engine life, but like anything in life, there is a trade-off. The process of filtration comes at a cost of air flow restriction in most cases. To overcome this you can use a larger filter or different filter media. Stock air filter elements are designed for long life and safe filtering of incoming air, not maximum air flow desired for performance engines. Most engine bays do not have room for larger filters so the best option for performance vehicles is a better filter media.

K&N filters are an example of a newer filter media that offers little restriction for the incoming air. Using an oil soaked filter media, the air is cleaned with little or no restriction in air flow. The downside is that the filter needs to be cleaned and re-oiled at regular intervals. This interval is dependant on your driving conditions. This is a small trade

off since you can re-use the filter media over and over again.

Not a new idea, but gaining popularity in recent years is the cold air intake. Your engine will make more power if the air entering the engine is cooler. This is because cool air is more dense than hot air. This allows more oxygen to enter the combustion chamber, which means you can burn more fuel. Cold air intakes were first popularized in the 60's with the introduction of the ram air hood scoops which manufacturers included on their hot models of the era. The idea was to scoop the air from the airstream flowing over the hood and ram it into the carburetor. While a good idea, there is debate about how well it really worked.

Modern cold air intake kits attempt to move the air filter away from the hot engine and suck air from in front of the engine compartment. This tends to work well if properly designed. You can check the design of the cold air intake with a simple outside thermometer available at you local Radio Shack store. The leads are long enough to place the readout in the passenger compartment allowing you to read temperatures while you drive. Place the probe at the original air filter location and drive around monitoring temperature at slow speeds and highway speeds. Then place the probe at the new intake position and you should see a large drop in temperature.

In conclusion, getting cool filtered air into your engine unrestricted is the first step to building more power in your engine. When shopping check for a high flow filter media and as large a filter as can be fit into your engine bay. A cold air intake is a good option if it really works!