All engines are developed to produce a certain amount of horsepower based on their physical characteristics. The most important features of an engine that effect power are the number of cylinders, the cubic displacement, valve layout and the delivery of air and fuel.

With millions of satisfied customers, for over 35 years, the Original K&N High-Flow Air Filter is still the #1 selling premium air filter in America. Once an "insider" product known only to racing and performance enthusiasts, today our High-Flow Air Filter is a mainstream product with clear benefits over disposable air filters

Most of our High-Flow Intake Kits for cars and trucks can be purchased for less than $350 and offer as mush as 5 times more horsepower than a K&N Air Filter alone. These air intakes provide dramatic increases in power and torque.

K&N offers several series of air intake kits designed for specific purposes and applications. This variety is how we ensure consumers can get what they want from the leader in High-Flow Air Intakes.

In 2009, K&N developed a 2nd reusable Hybrid air filter technology for use in heavy duty commercial grade vehicles like 18 wheel diesel trucks, agricultural equipment, earth moving equipment and some large class A diesel powered RV's. Our Commercial Grade Air filters are designed to increase horsepower and torque while strong enough for heavy duty turbo diesel applications.

Many of our customers write us about the mileage improvement they experience after installing our filters and intake kits. In our opinion there is a relationship between airflow restriction and mileage because energy is wasted when an engine has to work harder to suck air through the intake tubes and air filter.

This chapter explains how to safely and effectively increase both the performance and efficiency of your car's engine. If you are a more advanced enthusiast with a firm understanding of the fundamentals of car modifications and tuning, you'll find more information at KNFilters.com.

A listener calls Bobby Likis about his 2012 Chevy Truck & his need for better MPG.

Bobby Likis shares his personal testimony about the K&N products he uses.

In this K&N mailbag a listener just bought a 1996 Chevy Impala & is looking for some added growl under the hood.