The one product that all performance seekers can agree on is the aftermarket air filter. It's a fact that engines are basically glorified air pumps. Air gets drawn into the engine where it's heated, exploded and shot out the exhaust. Simple physics dictates that if you can get more air in, you'll get more air out; which makes more power in the process. This extra power can be used to improve performance-speed, mileage or otherwise.

A more powerful engine not only runs stronger, it runs more efficiently. So if the mileage miser keeps his foot out of the throttle, the power will translate to increased mileage. This is due to the fact that the more powerful engine has an easier time of moving the car.

There are many performance air filters to choose from, but most use the same basic design. About 30 years ago, K&N developed the cotton-gauze filter, which revolutionised the industry. This material lets more air pass, traps more dirt and lasts much longer than a traditional paper filter. Since then, most companies have taken K&N's basic design and tweaked it a bit to gain a market foothold.

So, when you're looking for that performance edge, whether it's speed, torque or mileage, a performance air filter should be your first stop. Your engine will run better, you'll experience results instantly and installation takes only minutes. You'll feel good about the upgrade and your car will thank you for it.