K&N® - 33 Series Air Filter

Nissan Altima 2.4L / 2.5L / 3.5L F/I 1993-2006, Air Filter by K&N®. Get better performance, superior engine protection and more economical operation just by changing your air filter. The K&N air filter gives you increased airflow without sacrificing filtration ability. It's the last air filter you'll ever buy for your car.

Features:

• Improves engine airflow
• Increases horsepower and acceleration
• Superior filtration without reduced airflow
• Reduces maintenance costs
• Washable and reusable
• Get up to 50,000 miles between cleanings under normal driving conditions
• Emissions legal in all States
• Backed by K&N's Million Mile Limited Warranty

Most air filters on the market are a compromise. Many high-performance filters deliver better airflow, but sacrifice filtering ability and engine protection in the process. OEM filters, which are usually made of paper, filter adequately but at the expense of airflow. And airflow decreases as these air filters become dirty. Not so the K&N air filter. K&N air filters increase airflow without decreasing filtration ability, and the increased airflow remains consistent throughout the filter's service interval. The secret is in the K&N filter's construction.

K&N's initial goal was to develop a filter that would deliver increased airflow during dirty, dusty off-road racing conditions. Increased airflow improves the efficiency of the combustion process, increasing horsepower and torque. But just increasing airflow without ensuring adequate filtration under those conditions would result in a ruined engine. K&N's solution was a filter design consisting of 4 to 6 layers of cotton gauze sandwiched between two aluminum wire screens. The cotton is then treated with a specially formulated grade of oil that causes tackiness throughout the cotton’s microscopic strands. The resulting K&N filter not only delivers increased airflow while trapping dirt particles that could harm your engine, that level of airflow is maintained even as the filter gets dirty. The layers of oiled cotton fibers in the K&N filter trap dirt particles that are smaller than the holes in the filter media. The thickness of the layers also allows the K&N filter to trap dirt and dust on many levels, trapping more dirt without decreasing airflow. Contrast this with a paper filter that only traps dirt on its surface; as the surface area becomes clogged, the airflow rate goes down.

Each K&N air filter is custom designed to fit into your existing factory air box. The K&N filter is economical because it's the last air filter you'll have to buy for your car. It can be washed and reused many times, and since you can usually drive up to 50,000 miles between servicing, you won't have to clean it very often. And every K&N filter is backed by K&N's Million Mile Limited Warranty.