K&N Audio Podcast Files

What Do I Have Under My Hood and Why Should I Care?

With very few exceptions, most cars on the road today are equipped with disposable paper or synthetic air filters. These are the filters that the automobile manufacturers install in cars when they roll off the factory assembly lines, and these are the filters that most service centers use as replacements when you bring your car in for service.

Feel free to check and see what kind of filter you have in your car. Unlike other automotive components like spark plugs and gaskets, the air filter requires no special tools to access and can be seen by simply unlatching the lid of your air box, generally found in an easily accessible location at the top of your engine compartment.

Once you remove the lid, you’ll find a flimsy, disposable air filter made up of pleated paper or synthetic material surrounded by a foamed rubber-like trim material. It is literally built to wear out and require replacement over and over. Why is it so flimsy and disposable? Well, because flimsy and disposable makes it cheap to manufacture and buy. Since it is cheap to manufacture and buy, automakers and service centers love putting them in cars. It keeps the price of the new car down, and because they need to be replaced, they keep customers coming back for scheduled service visits – a sure fire repetitive money maker for providing the same service over and over. This paper air filter, one of the cheapest components in your car, is a win-win for them -- cheap to supply, and a great way to bill for service – but a lose-lose for you, the consumer, because you are the one who is paying to keep replacing them. When you consider that the air restriction from a disposable air filter can rob your car of performance and that over 100 million air filters are thrown away each year, it’s easy to see why we invented a whole new technology.

Our cars deserve better and we deserve better. Our high-flow technology can increase power and acceleration while being reusable helps to prevent waste. If you’ve never been one to think about air filters, we hope to change your mind. The amount of air restriction caused by your air filter is directly related to the engine performance. Once you install a high-flow K&N Air Filter, you’ll never have to replace it and will have the peace of mind of knowing that you have the worlds best air filter under your hood from a company with 35 years of experience and millions of satisfied customers.


An Air Filter That Mattered

Historically, air filters have not received a whole lot of attention or comparative analysis. They were designed to provide adequate engine protection at an inexpensive cost – Hence, the disposable air filter covered the need. K&N’s understanding of the value and importance of engine performance led us down a very different path. A K&N Air Filter is not your run-of-the-mill cheap disposable paper air filter. In fact, it is not paper and it’s not disposable. The standard K&N High-Flow Air Filter is made of 4 - 6 layers of woven cotton gauze surrounded by 2 layers of coated aluminum wire. This filter medium is then framed with high quality plastisol or injected urethane for durability you can count on. Before it’s released for sale, the filter has a special oil treatment applied to the cotton to enhance its filtration efficiency. To say that a K&N Replacement Air Filter will outlast the life of your car is an understatement.

Ken Johnson and Norm MacDonald were professional off road motorcycle racers who like all racers had only one goal – they wanted to win. They also had a problem - the desert dust would so quickly clog a disposable air filter that they had to buy and replace a lot of them throughout a racing season. The K&N Air Filter was invented to help them win races and save money. They chose cotton instead of paper as the basic filtering medium because they knew cotton would flow dramatically more air into the engine and more air equals more power. The airflow was so high in fact, that other racers began to use K&N’s cotton air filter because it could mean the difference between winning and losing. In most applications, a K&N provided a measurable increase in acceleration and horsepower.

A secondary benefit of this cotton technology was long-life. Cotton is washable & reusable. The new K&N Air Filter could be used in dusty conditions, then washed, eliminating the cost of having to buy and replace disposable filters over and over again. Little did they know it then, but the technology was so durable that it would last for the life of a vehicle under normal driving conditions and one day be in millions of cars, trucks, SUV’s and of course motorcycles. When specially blended oil was added to the cotton, they found the missing piece. With oil the new K&N Air Filter provided outstanding filtration and engine protection, and the airflow rates were still awesome. Ken and Norm had given birth to a brand new air filter technology and still today we continue to invent new and clever methods for increasing horsepower, protecting engines and saving people money.

Oh, and in case you’re wondering, in those few cases where a K&N did not increase horsepower, it was because the air box or air path was the point of greatest restriction. We got around to solving that problem a few years later!


A Reusable Idea in a Disposable Industry

While other air filter companies sold disposable filters, asking consumers to waste money through the endless cycle of buy, throw away and re-buy. K&N took the road less traveled by selling consumers a million mile replacement air filter that fits in the factory air box It’s never easy being “first” or “different,” especially when standing against Fortune 1000 companies that were making over a billion dollars from the repeat purchasing of disposable air filters. Truly a “David versus Goliath” story, our task seemed impossible. We only had two things going for us; we built a better air filter and we were stubborn. 35 years later, we took a good deal of satisfaction from seeing one of the largest disposable air filter companies throwing in the towel and joining in our fight to convert consumers from disposable to reusable performance air filters. Today “Goliath” doesn’t seem so big anymore!


If You Want It Done Right, Do It Yourself

Later on in the CD, we’ll explain to you how an engine works and why a High-Flow Air Filter with low restriction can actually increase horsepower. But first we thought we’d answer the question we’re asked most often. What makes a K&N the best air filter in the world and what about these copycat filters that appear similar to a K&N? Our reputation has been built gradually based on the quality of millions of air filters we have sold over the years and the positive experience consumers have with our air filters after they install them in a vehicle. We take our filters very seriously and in the end the quality comes from the simple fact that we care. We are proud of this air filter we gave birth to and we do our utmost to excel in every way. K&N quality begins with the development and design of the product, it stretches into the manufacturing process and last but not least, we stand behind our replacement air filters and intake kits with the world’s first million mile warranty. Selling a product that performs as promised is a fundamental business principal of K&N. The information we put in print about our products, the horsepower claims, any data we expect a consumer to rely on in making their purchase decision is supported by documented test results either performed internally at K&N or by an independent laboratory. Talk is cheap and we read the same wild claims you do from time to time. But rest assured, there’s more to quality than just slapping some cotton between screens and adding color; otherwise, an old sock and chicken wire might just do the trick!

We’ll start with product design and engineering. There are several different ways to design a new air filter and rest assured not everybody does it the same way and not every design is bulletproof. One method would be to locate a vehicle, take the measurements of the air box, use them as the basis for creating a filter and voila! It’s time to start selling. A second method would be to acquire the O/E filter that comes with the vehicle when new and duplicate its dimensions in your air filter design. The third and most unreliable way would be to ask the consumer to trim the physical filter prior to installation. In our opinion, none of these approaches will ensure a properly sealed air filter once the air box is closed. A perfect fit and seal within the factory air box is critical to ensuring engine protection, otherwise, dirt will flow around the filter and directly enter the engine. O/E air boxes can be made of flexible materials and the very shape of the air box can be changed by its contents. This means a design that appears appropriate will only reveal shortcomings when placed in the actual air box and tested for fit, form and function. There have even been midyear changes to the air box during a particular vehicles production life. Our million mile replacement air filters are made from hard urethane and plastisol. Because our air filters are not made with flexible foamed trim material, they often require a more perfect fit than a disposable air filter. That’s why K&N part #’s do not always cross reference to disposable filters on a one to one basis. We may need to make several part #’s for vehicles that use only one part # from another brand.

At K&N, we always acquire the actual physical air box, design the filter, and install a prototype into the air box to test its seal against the air box over a series of days. You can be assured when we release a filter for sale, it has been tested to seal properly. After we have a first article of the air filter from manufacturing, it will be test fit a second time in an actual vehicle to confirm it is ready for sale. Needless to say, we design and develop our air filters and intake kits ourselves and do not rely on third parties in any way. Some air filters sold under a brand name are actually designed by a contract manufacturer who is providing a private label product to be sold under a familiar brand name. We believe that by controlling the entire development process, we are ensuring a lifetime of product quality. Our product development staff includes over 35 employees all dedicated to upholding the reputation of our brand name and the quality of our filter and kit designs. Ultimately, the reasons we can be so confident in our product is because we do the work ourselves and we know how to build a quality washable/reusable cotton air filter, because we invented it.

This same care and hard work is true for the manufacturing of our air filters. While other brands may sell disposable and/or reusable air filters that are manufactured by a third party, we build every air filter and kit we sell. When the box is closed at the factory, a K&N employee has verified it meets our own high standards. Our manufacturing is done in a 270,000 square foot plant in Riverside, California, which serves our North American markets. We also operate a 25,000 square foot plant in Warrington, England, that supports our European operations. Our manufacturing capabilities continue to evolve and we now incorporate state-of-the-art technologies such as in-house composite materials production using an autoclave, injection molded panel filter production, centrifugal molding, and multi-dimensional potted surface areas. Another unusual feature of K&N is our in-house machine shop from which we cut our own molds and even build our own production machinery. We currently offer over 3,000 individual part numbers for sale and offer a filter for virtually every vehicle on the road and off. The quality of our product is a point of pride among our employees and the absolute number one requirement from manufacturing. A K&N employee has physically inspected each and every air filter we sell before it goes into a box. This inspection is not just to verify proper manufacture, but to assure the filter is cosmetically pleasing. We scrap air filters that are perfectly functional simply because the pleats do not appear visually straight and uniform. Perhaps the greatest testament to our product quality is that over the last 35 years, we have sold over 20 million air filters. Our manufacturing expertise is something customers can continue to rely on to provide the best air filter their money can buy. So it’s easy for us to offer a million mile warranty on our replacement air filters and intake kits, we know they are built to last.


The World’s Best Air Filter Comes in RED and from California

It is very easy to build a filter that has a “K&N look” even if the materials used are completely different. It has gone on for years and we cringe every time we see a counterfeit product that is of low quality. We do feel a measure of pride for cotton air filters and hate to see the image of the technology tarnished by poor quality look-alike products.

So how do you tell the difference between the relative quality and capability of air filters? There are three basic ways to measure the differences between air filters.

The first way and a clear industry standard is a test of filtration efficiency commonly referred to as the ISO 5011 test protocol. Developed by the Society of Automotive Engineers, and since adopted by ISO, this is actually a test procedure or protocol with built in options. In order to compare two ISO 5011 test results, you need to understand which options have been selected. The test measures the percentage of dust retained by an air filter as the dust is introduced into a stream of air flowing through the air filter at a constant rate. There is an initial measurement and an overall measurement, both of which will be percentages. For example, a filter efficiency result of 95% means that the air filter retained 95% of the test dust allowing 5% to be passed through the air filter. The particle size and mix of the test dust used in a test is selectable by the test operator with certain mixes that are specifically defined by an ISO standard. For most applications, coarse test dust is used and is comprised of a precise mix of particles ranging in size from 5.5 microns to 176 microns. By way of comparison, a human hair width is approximately 50 microns, so even coarse test dust includes a significant amount of microscopic particles. We have an in-house testing apparatus that was built for K&N to perform the ISO 5011 testing procedure. This required a heavy financial investment in both the machine and personnel, but was critical to our on-going effort to build the best air filter in the world. Additionally, we occasionally send a sample of our filters to an independent laboratory to have the same test performed as an additional confirmation of our product quality. Some companies design their own dirt test to save the money of doing it right, but there is only one generally accepted standard test procedure and that is the ISO 5011 protocol. K&N Air Filters tested generally range between 95% and 99% in overall efficiency using coarse test dust. These numbers are very similar to quality standard disposable air filters we have tested over the years. We have tested a lot of air filters and seen results as low as 90% and as high as 99%. While there is no published research we have been able to locate on the relationship between engine wear and either particle size or air filter efficiency, our experience is a K&N Air Filter, like most disposable air filters, will provide all the protection an engine will need under normal operating conditions.

The second test of air filter capabilities is also measured using the ISO 5011 test protocol and is called capacity. Capacity results show how much dust the air filter can retain before reaching a point of air flow restriction generally held to be harmful to engine performance. Capacity is generally conveyed in grams and is impacted by several variables such as the technical performance of the filtration medium, the physical amount of filtration medium present, and size of the air filter itself. As an example, an air filter with a dust capacity of 250 grams means it will hold that much dust before cleaning or replacement is necessary. Our air filters are designed to have enough capacity to provide a cleaning interval of up to 50,000 miles for O/E replacement filters or up to 100,000 miles for our intake systems when used under normal highway driving conditions. Our O/E replacement filters are restricted in size to the original factory air box and filter size directly relates to the cleaning interval. On the other hand our intake systems use large oversized conical filter that can stretch the cleaning interval. Cleaning our air filters more often will keep air restriction lower throughout the life of the filter, thereby improving horsepower. However, we do not recommend cleaning them more often then every 15,000 miles since the performance increase is not worth the increased cleaning cost.

The third test historically overlooked by the entire disposable air filter industry is the amount of restriction created by the filter medium. Higher restriction means more engine effort is required to provide the engine with one of the four critical components of combustion, air! So how do you test something nobody ever cared enough about to even consider? In this area, once again, we had to invent the test. What we did was to largely follow a protocol that had been established for measuring the flow rates of cylinder heads and carburetors at a constant rate of restriction. We use a flow bench and increase the rate of airflow until restriction equals a pressure drop sufficient to displace 1.5 inches of a consistent quantity of water.. Never get confused between restrictions measured by the displacement of mercury. Mercury is approximately 13 times heavier than water, so it would truly be an apples and oranges comparison.. Of course it is in this test that the power of a K&N Air Filter reveals itself. Our filters flow substantially more air than a disposable air filter and that is where the horsepower and torque increase comes from. How much more? Consider this, using a Permeability test, a square inch of our filtration medium will flow 200 or even 300% more air than a standard disposable filtration medium. When translated into an actual air filter, this often means a K&N will flow as much as 30% to 70% more air.

The tricky part of the above three tests is that they are inter-related and the design of an air filter is constrained by the laws of physics. Generally, when you are dealing with the same filtration medium and the same filter size, the only way to increase airflow at a constant rate of restriction is to reduce filtration efficiency and vice versa. This means if you wish to have low restriction, you can design it for that. If you wish to have higher filtration efficiency, you can design it for that. You just can’t have both. The secret to a great air filter is to strike the right balance between airflow and filtration efficiency. When comparing air filters, you must always know all three numbers, efficiency, capacity and airflow AND you must know what options were selected for the test procedures.


A Natural and Remarkable Filtration Approach

It almost seems incredible that a cotton air filter can provide such high filtration efficiency while dramatically increasing airflow. When you pick one up and hold it to a light source, you can literally see light passing through the filter medium. It would be natural to assume this high flow medium sacrifices filtration ability and yet it does not. Here’s why. Our cotton air filters work on a principal found in nature. Multiple layers of filaments impregnated with oil. Fish gills use similar principals for extracting oxygen from the water, but an even better example is a human nose. Just like engines, humans need to breathe and keep dust from entering our lungs. When we run, we need to breathe more. The human nose filters dust by using many layers of hair that are once again impregnated with oil. If you want to look up your nose, do it on your own time, for now take my word for it. Our filters use 4 and sometimes 6 layers of woven cotton gauze . K&N gauze contains thousands of microfilaments that act like human hair. When impregnated with oil, those microfilaments provide a powerful filtration medium capable of maintaining airflow even while dust is retained. Instead of the dust particle blocking a passage and preventing further air flow through the passage, dust on a K&N Air Filter will attach to the oiled microfilament and then politely and temporarily move out of the way for future airflow. The next dust particle then finds its own “parking place” and the process continues. We call this depth loading - the dust is captured by a three dimensional “forest” of cotton fibers multiplied by 4 or 6 layers of material.


Cotton is More Complicated Than You’d Think

Just like nature, cotton gets complicated the deeper you look. How cotton is kneaded and combined at a strand level impacts how many microfilaments are contained in a linear inch. How closely the cotton strands are woven together impacts its filtration, capacity and airflow capabilities. Imagine a grid of yarn that looks like a checker-board. Each square is a certain width and height that was determined by the original weave. Larger “Squares” flow more air and trap less dirt. Smaller squares do the opposite. Obviously, the layers of cotton affects everything as well. There can even be absorbency differences in different grades of cotton, which has a direct impact on how well the oil can remain within the medium. At K&N, we have had 35 years of experience understanding and testing many variations of cotton, weave counts and oils. We know how to work the variables to achieve the best overall result. A remarkable fact is that a cotton air filter can be either a poor or a great filter depending on the micro details and judgments made in the selection of cotton.


Cleaning Your K&N Air Filter

All K&N Air Filters are washable and reusable. Your normal driving environment will determine when you should clean your air filter. If you drive under normal highway conditions, we recommend you inspect your filter every 50,000 miles. If you occasionally drive on dirt roads, we recommend you inspect your filter every 30,000 miles. Extremely dusty conditions such as driving regularly on dirt roads would require even more frequent inspection. A filter inspection does not necessarily mean it needs to be cleaned. An inspection should be visual to identify the amount of dirt build up on the filter. There will always be dirt and this can even help filtration. Only when the dirt build up becomes excessive should you make the decision to clean the filter. A K&N filter can accumulate dust up to 1/8th of an inch before cleaning is required. The easy way to make this determination is to see if you can visually identify all of the visible aluminum wire mesh on the top of the pleats. If it is still visible, the filter does not yet require cleaning and can be replaced in the vehicle. The next subsequent inspection should occur in 5,000 to 10,000 miles, once again, depending on driving conditions. Once the aluminum wire is covered with dirt and no longer visible in some places on the exterior of the filter, it’s time for cleaning.

When cleaning the filter, first gently tap the filter on the ground or another hard surface to remove any loose dust that will easily fall off the filter. Next, thoroughly saturate the filter medium with K&N’s Air Filter Cleaner. Then let the filter set for approximately 15 minutes. After that, take a garden hose or low pressure water source and from the inside of the filter out, wash off the dirt. Flushing from inside out is the best way to remove the dirt from the medium. Next, shake the water out of the filter and let the filter dry for several hours. A non-pressurized air source such as a common hair dryer, operating without heat, can be used to accelerate the drying time. Pressurized water, air or heated air can reduce the number of cotton microfilaments reducing the filtration ability of the filter in the future and should never be used. When the filter is dry, it needs to be re-oiled using K&N Recharger Oil. We recommend using our Recharger oil that comes in a squeeze bottle because this provides the most control over the amount of oil applied. When using the squeeze bottle, simple apply a bead or line of oil along the top only, running the entire length of each pleat of the air filter. The oil will over a short period of time soak into the rest of the filter medium because cotton is very absorbent. For those of you who want to use our aerosol Recharger oil, lightly “paint” the filter surface with one coat of the aerosol spray. Do not over oil a filter because this can increase restriction undermining the benefits of our High-Flow technology. A filter should never be dripping with oil visibly running off the filter. After oiling, we recommend you gently tap the filter to remove any excess oil and allow the filter to set for a few hours. While this setting time is not a requirement for a properly oiled filter, it will reduce the likelihood of over oiling and is never a bad idea.

Remember, there are a few things you do and do not want to do to a K&N Air Filter because they will cause damage to the product and reduce the service life. Our air filter cleaner has been specially formulated for the specific task of cleaning our cotton air filters. Other cleaners are not recommended and could, depending on the cleaner used, damage the filter. Feel free to use our cleaner to remove grease and oil from your driveway, it works great, but save some for our air filter, which it is designed for. Do not use gasoline or caustic cleaning solutions. Do not use steam cleaning equipment nor car wash devices; pressurized equipment will strip the cotton of those critical microfilaments. When drying the filter after cleaning, your best bet is to let the filter dry naturally. Please do not use compressed air, open flames or heating devices of any kind. If you’re really in a hurry use a hair dryer with no heat. When Recharging the filter with oil, we recommend you use K&N Recharger oil. Once again, it has been developed for our filters and is the same oil applied at the factory during the manufacturing process. Do not use transmission fluid, motor oil, lightweight oil, or diesel fuel.


The World’s First Million Mile Warranty

Our replacement air filters and Intake Kits are built to last for the life of your vehicle and are backed up by the world’s first million mile limited warranty. If a customer ever experiences a problem with their K&N Air Filter or intake kit, please have them contact the K&N customer service department directly and we will take it from there. We will repair or replace the product once we have confirmed proof of purchase. This can be done by a customer filling out a warranty registration card at the time of original purchase or by simply giving us a copy of the receipt for the purchase. We invented the very concept of the million-mile warranty to give consumer’s confidence that when they buy K&N, they are buying the best.


Consumer Protection Pledge

We want to make sure that when you buy a K&N Air Filter or Intake System, you can be confident your vehicle's warranty will not be impacted. We also want you to feel confident that even if you experience a unreasonable dealership, we will step-in and resolve the issue, so you won't have to. Therefore, we make the following Pledge:

K&N pledges to our customers that they will not be taken advantage of and charged for a repair due to a dealership warranty denial blamed on the presence of a K&N product.

A frustrating problem we occasionally face is service technicians making false or unsubstantiated claims about aftermarket products, even something as standard as a K&N air filter going in the factory air box. These false allegations may then used as a reason to deny a legitimate warranty claim and force a consumer to pay money when they should not have to. We are horrified that the presence of aftermarket products could in rare instances be used as an excuse for taking advantage of a consumer. In all instances we have experienced so far, the dealership’s position is mere speculation unsupported by any evidence. However, the dealership is in the “power position” and more often than not, they will win this unfair fight with a consumer, who needs their vehicle back. We are going to balance the scales a bit. We will use our resources to make the consumer whole and challenge the dealership. If you have any problem at all with a K&N product or a service provider, please call us immediately and we will help.


Vehicle Warranties

Our air filters will not void a vehicles manufacturer’s warranty. They are high quality replacement parts and automotive or motorcycle dealerships cannot void a consumers warranty solely based on the existence of an aftermarket product. The law covering this issue is the Federal Magnuson-Moss Act. There only two ways in which a dealership can void a consumer’s warranty, the first is if the part in question is made available to consumer’s free of charge by the OE manufacturer. The second is if the Dealership can prove the aftermarket part has caused damage to the vehicle. The burden of proof is on the dealership even though they may attempt to shift that responsibility to the consumer. We have certainly heard the rumor that an over oiled K&N Air Filter can cause a failure of a vehicles Mass-Air Flow sensor. We have spent a great deal of money investigating this allegation. We have worked with dealerships and the OE’s and retrieved sensors they claimed were fouled by K&N Air Filter oil. When the sensors were tested both by an independent lab and at K&N, the results were that the K&N Air Filter was not to blame for the failure. We view this allegation as strange and unsubstantiated. Stranger still, some of the “bad sensors” we tested were in fact in perfect working order. Our investigations have revealed that often dealerships do not even have the equipment necessary to determine the cause of a sensor failure.

So have a consumer immediately contact our customer service department if they run into any vehicle or mass air flow sensor warranty problems. More information on this issue is available on our website KNFilters.com.


Finding the Right Part For Your Vehicle

This is a challenging issue for the entire industry because historically, there have not been standardized descriptions of different vehicle configurations or applications. Fortunately, at K&N we have a great application lookup tool available at our Web Site KNFilters.com. All our application information now complies with the new AAIA standard and can be transmitted electronically. We have over 300,000 visitors to our web site each month to find the correct part for a particular vehicle application. Since we release an average of 30 new part numbers each month, our web site is the best place to get the most current application information and most up to date part numbers.


How K&N Air Filters Can Increase Horsepower

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. Air is a necessary ingredient to the combustion process of an engine and the more air molecules the better. The job of an air filter is to significantly reduce the amount of dust entering an engine while providing adequate airflow for the combustion process. As an air filter accumulates dust, its ability to flow air will eventually decrease. This is true for all filters regardless of type. That is why a dirty air filter can degrade performance or cause a vehicle to become sluggish.

When it comes to air filters, bigger is always better. Filtering capacity and air flow increases, as an air filter’s surface area grows larger. This is true for both high-flow reusable air filters and disposable air filters. Given the same filter medium, a bigger filter size with more surface area will always provide more airflow and a longer service life. Comparisons of filter size between filters of different types are not generally meaningful because of the different capabilities of the alternative filtering material.

We invented our washable/reusable High-Flow Air Filter to offer reduced restriction and increased airflow over disposable air filters while providing all the protection an engine needs. This increased airflow of a K&N is the direct result of our cotton air-filtering medium, which is fundamentally different than traditional paper air filters. To understand this difference, compare breathing through a t-shirt to breathing through a piece of woven paper.

Engine airflow restriction can occur in several ways. Air Flow Filter Restriction will be increased or decreased based on the type of air filter used. Air Box Size Restriction can occur if the factory air box that contains the air filter is simply too small for a vehicle’s engine. The smaller factory air box limits the size of the air filter and therefore can starve the engine for air regardless of air filter type. Finally, Air Path Restriction can occur inside the airway path that runs between the air box and filter and the engine. This arises from the number of bends, tube diameter and sound baffling built into many factory designs.

The first way of reducing restriction is by switching from a disposable air filter to a High-Flow K&N Air Filter. The second way is to eliminate the factory air box with a 57i or 57 Gen I FIPK. The best solution is to use a complete air intake system, such as our 57 Series Gen II FIPK, 63 Series AirCharger^®, 69 Series or 77 Series metal intake kits. Each includes an oversized conical K&N Air Filter and a specially designed tube assembly that reduces turbulence and drives air into the engine for increases in horsepower you will feel. While many of these intake systems are street legal in all 50 states and CARB exempt, certain intake systems we sell are not legal for use in California or other states adopting California emissions standards. Please check our website or catalog for the specific CARB status of each system we sell on specific vehicles.


Air Filter Product Lines

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. We design and manufacture every air filter we sell because it’s our reputation that’s on the line.

Over 100 million disposable air filters are thrown away in this country every year. These trashed filters go into landfills and incinerators contributing to our nation’s growing waste burden. The U.S. Environmental Protection Agency (EPA) recommends using reusable air filters as an effective means of reducing waste. At K&N, we make only washable/reusable air filters. Increasing power while reducing waste is our goal.

We sell thousands of different air filters for everything from radio-controlled cars to monster trucks. Our air filters fall into three basic categories so take your pick!

O/E REPLACEMENT AIR FILTERS
We sell over 1,200 different replacement air filters for virtually every vehicle on the road. These filters are custom designed to fit into the existing factory air box. Their drop-in design means adding performance is simple. All a consumer has to do is remove their disposable air filter and replace it with a K&N; there is NEVER any cutting or fitting required. Our stock replacement air filters are covered by our famous K&N Million-Mile Limited Warranty^TM.

Our goal is to offer an O/E replacement air filter for every vehicle on the road. We believe our O/E replacement air filters are simply a better technology than disposable air filters. The only reason people may not have one yet is because they don’t know about all the benefits K&N provides - better engine performance and a great value because they never need to be replaced.

UNIVERSAL & CUSTOM AIR FILTERS
With over 1,100 different part numbers available, we offer a universal filter for just about every need. Dimensionally designed and classified by size, shape and style, these air filters are intended for just about any air filter use imaginable. Certain filters are available with metal, chrome or carbon fiber lids. Some are even available with our patented XStream^TM filter top, which means the lid is an air filter itself. Professional racers, automotive builders, and enthusiasts of all types use K&N Universal air filters. Increasingly many consumers are using these to replace look-alike K&N filters on all types of intake kits. If we don’t fit a requirement, call us up and we will find a solution that will work for you.

These filters are not application specific in nature. They are designed for the enthusiast who needs a High-Flow K&N Air Filter for a specific or custom engine requirement. When the airflow requirement of the engine is determined, customers can use a formula we provide to calculate the minimum size air filter that will meet their engine requirement. Most universal air filters are attached to an engine by clamping the base of the filter to the carburetor or throttle body. Our universal filters are typically made of four layers of cotton gauze molded into plastisol for maximum durability and high airflow. Our one-year, unlimited mileage “K&N Racing and Off Road Limited Warranty” backs our universal air filters.

RACING AND SPECIALTY AIR FILTERS
These filters have been developed to meet the unique requirements of a racing environment. They are flat out designed to give the racer a competitive edge. Our racing filters are perfect for any situation that demands high airflow, engine protection and light filter weight. Over the years, we have shown that running a K&N Air Filter can generate more power in some cases than having no air filter at all. This is due to our filters ability to reduce turbulence at the intake port. These filters are used in almost every form of racing around the world. We offer over 100 different Racing & Specialty Filters backed by our one-year, unlimited mileage Off-Road and Racing Limited Warranty.

The materials used are what set these apart from other K&N High-Flow air filters. Carbon fiber, Kevlar^TM, titanium or aluminum is used for the main structure of the air filter. The filter material ranges from 2 to 6 layers of cotton gauze covering every need from street racing to extreme dirt racing conditions. All of these filters are custom designed for a particular engine size and racing environment. For certain dusty applications, we recommend using our DryChargers as an exterior wrap to provide extra protection and capacity for dirt. These Wraps are made from special nylon fitted to the filter. They can be routinely removed and cleaned and will not significantly reduce airflow.


K&N Intake Kits –The Ultimate in Horsepower

Most of our High-Flow Intake Kits can be purchased for less than $350 and offer as mush as 5 times more horsepower than a K&N Air Filter alone. These kits provide dramatic increases in power and torque. On the 2003 Ford Mustang SVT, we actually achieved an increase of 30 horsepower. Even our typical kit gains are in the range of 8 to 16 horsepower on a V-8 Engine. When you realize that an average V-8 Truck traveling down the road at 55 mph uses about 17 horsepower, you begin to understand how much more power we can provide. We’re proud of these kits because after you bolt one on, you’ll know something’s different with your car or truck…VERY DIFFERENT!

Most people are aware that our High-Flow Air Filter can increase horsepower over a traditional disposable air filter. An air filter change alone however, cannot eliminate other types of air restriction built into the vehicle at the factory. These can be found in the size of the air box and the air path running from the air box to the engine. That’s where intake kits rule the road. They completely replace the factory airflow assembly including the filter, air box and air path. More and more people are discovering the monster power available from a well-engineered intake kit and we sell over 200,000 intake kits every year, so go ahead and wake the sleeping giant in your car.

We will not sell an intake kit that does not provide a measured increase in horsepower and torque (Acceleration). Each kit is proven to increase horsepower and torque on a wheel based dynamometer (think treadmill for cars). These thoroughly engineered kits provide huge increases in power that a customer will definitely feel when they accelerate.

Instead of lofty claims, we provide actual horsepower increases available from our kits on specific vehicles. This way a consumer can know what they are buying and what they will get. Consumers can find this horsepower information in our new POWERBOOK or by visiting us at KNFILTERS.COM.

These kits are easy to install. A typical installation can be done with a screwdriver, pliers and a ratchet set in 90 minutes or less. We specifically engineer these kits to use factory holes and mounting points making installation simple. The vast majority of our kits do NOT require any cutting or drilling.

All our kits include oversized K&N conical air filters. Because of their greater surface areas, they can go up to 100,000 miles between cleanings, depending on driving conditions.

Every kit we sell is street legal in most states. California and a few other states require an intake system to be inspected by a state regulatory agency, such as the California Air Resources Board (CARB). If the system meets the regulatory requirements, CARB will issue an EO number. This number, when referenced, will inform a smog inspector that the intake system does not cause the vehicle to be in violation of state emissions standards. EO numbers are assigned for a specific part number on a specific vehicle. When a new year of the vehicle is released, a resubmission to CARB is required. The time required to go through the regulatory process can be as great as ten months and there is no guarantee the system will be found acceptable for each successive vehicle model year.

While many of these intake systems are street legal in all 50 states and CARB exempt, certain intake systems we sell are not legal for use in California or other states adopting California emissions standards. Please check our website or catalog for the specific CARB status of each system we sell on specific vehicles.


Intake Kit Product Lines

We offer several series of 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.

57 Series and 63 Series Intake Kits
Our 57 Series FIPK and 63 Series Air chargers are built for many different vehicles and represent a dramatic improvement over a K&N O/E replacement filter alone; they use only non-metallic rotationally molded tubes that can reduce air temperature and decrease intake sound over a metal tube. The aerodynamically engineered tube drives a massive amount of air into an engine, which translates into POWER.

Both these series are truly state-of-the-art. We start with the largest conical shaped High-Flow air filter we can fit into the engine compartment while using factory holes and mounting points. This extra filter size provides even more airflow at lower restriction than a standard K&N O/E replacement filter that is limited to the size of the factory air box. The oversized air filter also captures and holds more dirt increasing the service life before cleaning is required (up to 100,000 miles). When possible, the filter is isolated from high engine temperature by a heat shield designed to lower the temperature of the air entering the engine, which increases horsepower. Next we attach the filter to a rotationally molded tube made from interlaced High Density Polyethylene (HDPE). This process allows us to precisely shape the tube and reduce turbulence and accelerate airflow into the engine. This is why some of our tubes have unique shapes that are specifically engineered for each application. Finally the tube is connected to the engine with adapters made from high strength materials such as silicon and reinforced nylon and ensures long life. Put all this together and you have the best high-flow intake system available today.

57i Series Intake Kits

57i Series Intake Kits are specifically designed for each different vehicle and will free your car from the size restriction that comes with the factory air box. These economical kits can take a variety of different forms based on vehicle characteristics and available space under the hood. Each kit is designed to provide power throughout the RPM range. Gen I’s take advantage of the added airflow provided by an oversized air filter released from the restrictive factory air box.

These kits bring engine airflow out of the factory box by providing a large size open-air conical or round High-Flow Air Filter. The extra surface area of these open-air air filters provide even more airflow at lower restriction than a K&N O/E replacement filter which is always limited to the size of the factory air box. The larger air filter also captures and holds more dirt increasing its service life before a cleaning is required (up to 100,000 miles). The filter is then either directly attached to the engine carburetor or throttle body or indirectly through a tube assembly running from the filter to the engine. All adaptors are made from high quality materials such as steel, aluminum, silicon or reinforced nylon and ensure long life.

69 Series Typhoon^® Intake Kits
Our 69 Series Kits for automobiles and sport car applications are offered in many different colors and styles, these kits offer an opportunity to customize a car to achieve that show quality appearance. Many consumers will opt for the visual appeal of these kits that make a statement the minute you open the hood. These metal tube systems also offer a completely different sound from a plastic tube, louder and with a definite ring!

Our 69 Series kits are truly hand-crafted pieces of art. Available in an assortment of powder coated colors and bright aluminum, these kits are sure to please in every way. They come with an oversized High-Flow conical air filter designed to provide increased surface area and dust capacity. This extra surface area provides even more airflow at lower restriction than a standard K&N O/E replacement filter that is limited to the size of the factory air box. The oversize air filter also captures more dirt increasing the service life before a cleaning is required (up to 100,000 miles). Some kits include a heat shield. All of our 69 Series intake kits use adapters made from high strength materials such as silicon and reinforced nylon and ensures long life. These kits also come standard with stainless-steel barrel-locking hose clamps and powder coated steel brackets.

To help consumers customize their vehicles and achieve that show like appearance, we offer several different styles of tube options in this product line. Short Ram Intakes use a shorter tube length to protect the filter from adverse weather conditions and accommodates the existing engine bay space. Cold Air Intakes add a heat shield and use a medium length tube designed to capture cooler air within the engine bay for added horsepower while using factory-mounting points. Complete Cold Air Intakes use a two-stage extended length tube. When using only one tube, the kit will act as a Short Ram version. With both stages installed the extra tube length will extend beyond the engine bay away from the heat of the engine to maximize cool air, which is a key ingredient for horsepower. The Cold Air Intakes and Complete Cold Air Intakes include a DryCharger Filter Wrap designed as a pre-filter to protect the air filter from extreme dust or weather conditions.

77 Series Metal Intake Kits
Our NEW 77 Series metal Intake Kits for trucks and SUV’s combine outstanding performance and under-the-hood style. Many consumers will opt for the visual appeal of these kits. The metallic finishes are bold and beautiful. Metal systems also offer a different sound than plastic tubes.

Our 77 Series kits are truly hand-crafted pieces of art. Available with bright aluminum or gunmetal grey powder coated tubes, these kits are sure to please in every way. They come with an oversized High-Flow conical air filter designed to provide increased surface area and dust capacity. This extra surface area provides even more airflow at lower restriction than a standard K&N O/E replacement filter that is limited to the size of the factory air box. The oversize air filter also captures more dirt increasing the service life before each cleaning is required (up to 100,000 miles). Most 77 Series Kits include a heat shield designed to seal against a vehicle’s hood to isolate the air intake from engine heat. Cooling the air that travels into the engine can increase horsepower all by itself. All our metal intake kits use adapters made from high strength materials such as silicon and reinforced nylon and ensures long life. These kits come standard with stainless-steel barrel-locking hose clamps and powder coated steel brackets.

While many of these intake systems are street legal in all 50 states and CARB exempt, certain intake systems we sell are not legal for use in California or other states adopting California emissions standards. Please check our website or catalog for the specific CARB status of each system we sell on specific vehicles.


Commercial Grade Reusable Diesel Air Filters

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

In 2005, we began a journey to develop an easily cleaned, high-flow, commercial grade air filter. The result is our new Hybrid Filtration Medium; a non-woven synthetic material with a difference. Many non-woven mediums have a two-dimensional or “flat” surface. Our Hybrid filter media is comprised of lofted non-woven synthetic fibers held between aluminum screen. This three dimensional platform uses two features we adopted from our cotton air filters; depth loading and structural screen support. These are the two primary elements that promote higher airflow and larger dust holding capacities.

Our Commercial Grade Air Filters are incredibly easy to clean. After you apply our special degreaser, you can use pressure washers, compressed air, or water hose nozzles to clean the dirt and grime out of the filter. The filter does not even have to be completely dry to be re-installed.

These air filters a specifically built to withstand the power and compression typical of large turbo diesel engines. The Hybrid filter medium is pleated and placed between two powder-coated aluminum screens for consistent surface area that can smooth and straighten air flow. The pleated media is then surrounded by a powder-coated steel cage.

We think our commercial grade air filters are a great alternative to disposable heavy duty air filters that deliver on multiple fronts; more power, reusable and easy to clean.


Mileage

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. However, a 2009 study performed for the US. Department of Energy found that “replacing a clogged air filter on cars with fuel-injected, computer-controlled gasoline engines does not improve fuel economy but can improve acceleration time by around 6 to 11 percent. This kind of engine is prevalent on most gasoline cars manufactured from the early 1980s onward.” The results of this study did “suggest that replacing a clogged air filter on an older car with a carbureted engine may improve fuel economy 2 to 6 percent under normal replacement conditions or up to 14 percent if the filter is so clogged that it significantly affects drivability.

Clearly, based on the U.S. DOE study, you should not buy a K&N air filter believing it will improve the mileage of your car. We recommend people buy our air filters for added engine performance and the benefits of having a reusable air filter that can reduce waste and save energy.

There are many other variables that do affect mileage such as: tire inflation, the type of fuel, weather, elevation, the speed at which you drive, the gear in which you drive, the speed with which you accelerate, engine maintenance, excessive idling, cruise control, and the grade of motor oil you use.


How Your Engine Works, Air Flow and Horsepower

If you are curious about how to go about getting more performance out of your car, or just have been taking your first steps in modifying your car for more power, then this section is for you. In it, I will present a primer for safely and effectively increasing 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 the K&N White Papers at (KNFilters.com) to be a more technical look at the how’s and why’s behind the performance basics covered here.

While automotive enthusiasts often have visions of some day becoming a mad scientist in the garage, or perhaps part of a finely honed pit crew in an F1 race, the better analogy to start with is a chef baking a cake. So don your imaginary chef’s hat for a moment, and I’ll explain how working with the internal combustion engine is a lot like baking a cake.

Baking a cake requires four basic ingredients -- sugar, flour, eggs and butter – mixed in the proper amounts relative to how big a cake you will be making. So, too, the engine in your car relies on four basic ingredients -- air, fuel, spark and timing – mixed in the proper amounts relative to how much power you will be making.

Let’s say I was to begin baking a cake that serves two people. I would use a ratio of the four cake ingredients above as appropriate to the serving size. Now let’s say that as I’m in the process of baking my cake, I get a phone call and learn that two more friends will be stopping by, and I will need to double the amount of cake that I have. It is not enough for me to add twice as much flour, for example, without also doubling the amount of eggs, sugar and butter in equal proportions, or my cake will be ruined. It seems a simple point to make, but in reality, behind all the glitz and glamour of manufacturers selling expensive and shiny parts to bolt-on under your hood, this point is almost universally the first one that is overlooked. Note that adding power under the hood is never a matter of simple math (for example, that if advertising materials or magazine articles tell you that a certain exhaust adds “up to” 10 horsepower, an intake 5 horsepower, and a chip tune another 15 horsepower). While it is true that each component will add performance and compliment the others, the net result wills rarely, if ever, total 30 hp as the numbers might otherwise lead you to believe.

So, if your goal is to have your cake, and eat it too, be mindful of how parts you add under the hood change the ratio of ingredients to each other. So what is the correct ratio? Well, this is going be different for each car, depending on whether your car is outfitted with forced induction (for example, a turbocharger or supercharger), the compression ratio of your motor, and the tolerances that vary between manufacturers and according to the mileage and condition of your motor. However, most every engine has room to safely and reliably make more power, whether it’s double or triple the amount that they came with from the factory, or just a mild improvement, before experiencing added strain and a considerable impact on reliability and longevity. As a rule of thumb, a 5-10% increase from the amount of power your car makes, as delivered to you, is within the realm of safety. Nearly all engine components, regardless of the manufacturer, are designed with tolerances sufficient to withstand, on average, at least a 5-10% improvement in peak power.

I’m Ready for More… Where to Begin?

The internal combustion engine, as the name implies, relies on an explosion, or more specifically, a series of carefully timed explosions, to generate the power that moves your car down the road. These explosions consist of a mixture of air and fuel, ignited by spark, at precisely the right time. By altering the amount of air, fuel, spark, or timing, you are in effect creating a bigger explosion, and that bigger explosion generates more power. A car with a mild to moderate increase in power doesn’t have to be any less fuel efficient or any less reliable than the one that makes less power – but it does take a careful chef, one that uses only the finest ingredients, and ensures that the car is well maintained and in sound mechanical condition. If your car is exhibiting any signs of fatigue, adding more power is going to make matters worse, not better. Make sure your car is in top condition before moving on to bake the bigger cake. After all, there is no point in pouring ingredients into a pan that has a hole in the bottom.

Assuming you are ready to begin adding power, the first ingredient to go into the mix is air. In essence, your engine is a giant air pump, and the quantity of air that your engine is able to take in from the intake, and expel out of the exhaust, is directly proportional to the amount of power you will be able to generate. One analogy that I have heard used in performance circles for some time now is a marathon runner. Imagine your car’s air intake is the marathon runner’s lungs. A restrictive intake is the equivalent of a marathon runner trying to breathe through a tiny straw. A less restrictive intake allows him to breathe freely, and run much faster.

Since most factory intakes are designed around cheap, disposable air filters that choke off the engine, a simple filter change to a high-flow air filter is often the very first modification involved in making more power. K&N offers two ways of allowing your engine to breathe more freely and efficiently. A K&N factory replacement drop-in filter allows you to simply exchange the disposable filter element inside your factory air box with a high-flow cotton gauze lifetime filter that provides excellent filtration, yet presents less of a restriction to incoming air than disposable paper filters. Although a K&N lifetime filter costs a little more initially, you’ll be saving money in the long run since you never have to change it.

Beyond a drop-in filter, K&N also offers a series of Intake Systems as a next step in performance. These replace not just the filter element, but the entire maze of restrictive factory intake piping, with an open element air filter connected to a short, straight section of piping designed to bring the maximum amount of air into your engine. Intake Kits are popular upgrades both because of the significant improvements these make to the amount of air available to the engine, as well as the fact that they free up space under the hood, allowing for a more aesthetically pleasing engine compartment, and easier access to other engine components during routine service and for other mechanical upgrades.

Good air in - bad air out

Because your car is breathing more efficiently with the K&N filter installed, it is also a good idea to remove the restriction in the exhaust path to allow the additional air to exit smoothly and efficiently after combustion. Since the exhaust system consists of several components, including the exhaust manifold, down pipe (on turbo cars), b-pipe (or intermediate pipe), and ultimately the portion behind the rear axle terminating with the muffler canister and exhaust tip (known as the axle back), these components can be upgraded either individually, or all at once. However, because catalytic converters are present in the exhaust path to help clean up hydrocarbons and reduce emissions, if the vehicle code in your jurisdiction requires the use of emissions control devices, there are likely regulations in place concerning the legality of exhaust modifications to the catalytic converters themselves as well as the exhaust system upstream from the catalytic converters (the exact location will vary from car to car). At K&N, we encourage respect for the environment, and strongly discourage tampering with emissions control devices. Further, emissions technology has advanced to the point where in most cases; only nominal gains can be achieved by removing or tampering with catalytic converters.

Adding fuel to the fire

With the first ingredient in our recipe for a bigger serving of power, the ratio of air to fuel has changed. Fortunately, most late model engines are run by a factory ECU (Engine Control Unit) capable of adjusting fuel delivery to maintain a consistent ratio of air and fuel, even with a more free-flowing intake and exhaust.

However, if you have added even more air than just the filter itself – for example, in the form or a turbocharger or supercharger, the additional air volume will be well outside of the factory ECU’s ability to compensate (known as its enrichment parameters). Depending on how much additional air is being brought into the engine, the necessary fuel upgrades may consist of higher capacity fuel injectors, a bigger fuel pump, and/or a rising rate fuel regulator. In addition, the ECU will need to be optimized for this hardware. I will discuss the ECU’s role later, but for the time being, it is sufficient to say that any time dramatic changes are made to the amount of available air or fuel, the ECU will need to recalibrate the air, fuel, timing (and where applicable, boost) maps accordingly. Failure to install the appropriate fuel support modifications and recalibrate the ECU will most likely result in an overly lean air fuel mixture (too much air, relative to fuel). A lean mixture will burn too hot and in turn, lead to detonation (a condition in which the air/fuel mixture is too easily lit off at the wrong time) and major engine damage will likely result.

We have ignition!

With the appropriate amount of air and fuel in the mix, the next step in our recipe for power involves controlling the spark that ignites the mixture. Earlier, I commented on the importance of ensuring that the car is in top shape before attempting to go for more power. Perhaps that best example of the importance of a properly maintained engine is the ignition system. If you have not changed your sparkplugs and plug wires recently, along with your ignition cap and rotor (for car’s with distributor equipped ignitions), chances are good that your air/fuel explosion is being compromised and that you are getting a less-than-optimal burn of your air/fuel mixture. Without making any other changes to your car, you should find a noticeable improvement in both power and mileage simply by switching worn ignition components to fresh ones. Of course, if you are adding significant go-fast hardware under the hood for dramatically increased air and fuel capacity, a simple set of factory specification components may not be enough to ensure a clean burn for the mixture. In this case, you will want a stronger spark, coupled with a cooler spark plug, to best avoid fouling your spark plugs with air and fuel that has not been burned, transferring too much heat into the cylinder head, and/or not getting a complete burn of the available air and fuel.

In most cases, this can be remedied by switching to a spark plug that it is one to two heat ranges colder than those that came with your car from the factory. The heat range of spark plugs denotes the thickness of the porcelain insulators, and thus, their ability to transfer heat away from the cylinder head. You will also want to consider running a larger plug gap to expose more of the air and fuel to spark during combustion. However, in order to do so without immediately fouling the plugs (drenching them in fuel and rendering the electrode ineffective) you’ll want to consider adding an after market ignition amplifier consisting of a control box that uses either the factory ignition coil (or coil packs), or upgraded coil packs, to provide more electrical capacity to your spark. Different systems operate on very different principles, including firing the spark in rapid succession bursts, or simply storing and sending more spark energy to the plug through the coil (or coil packs), or some combination of the two, but the general idea is the same – more spark, for a bigger and more carefully controlled explosion.

Not every car will need extensive ignition upgrades. Many cars have very robust factory ignition components capable of sustaining horsepower levels that are often as much as double or triple the factory power figures. However, for other cars, this area is very much an Achilles heel. When in doubt about whether your car will benefit from expensive ignition upgrades, consult with a qualified tuning professional (local shops that offer “dyno” tuning services should be able to point you in the right direction and there are some terrific resources online in the form of car message boards for nearly any make and model of car).

Timing…. Is Everything

Your car’s ECU (Engine Control Unit), is the central command post that dictates when, how and for how long these other ingredients (fuel, air and spark) are combined in the recipe for more power. Again, like baking a cake, it is not enough to say mix the batter and bake it, the recipe itself should tell you in what order the ingredients are added, and for how long to bake it at what temperature. Of course, this is a gross oversimplification of what the ECU is actually doing. The ECU is continually making calculations and adjustments within fractions of a second based on feedback it receives from the car’s sensors, including the oxygen sensor, airflow meter or mass air pressure sensor, knock sensor, coolant and air temperature sensors, and a host of other input variables. Imagine if baking the cake involved measuring the temperature in the room, altitude at which you will be baking, relative humidity that day, whether there is any background noise while you will be cooking and the relative quality of the butter and flour that you intend to use, and performing a series of algorithms before telling you what temperature to bake your cake and how long to keep it in the oven.

So how does the ECU make these determinations? Quite simply, it continually refers to a fixed set of base tables to which it references back in establishing the burn characteristics for the air/fuel/spark mix. These base tables need to be modified as the under hood components themselves are changed, and a qualified tuning professional can help advise you on the best method for making these changes, as well as point you to a dynometer (or rolling road) to simulate the variables your car will encounter under load as you drive. Depending on a number of factors, including your budget, expectations, and the extent of your modifications, your preferred method of ECU control may be a piggyback controller that intercepts the 0-5 volt signal from your factory sensors and tweaks them before sending them on, a chip replacement or reflash that permanently installs a new set of maps in your ECU, or a standalone ECU that replaces your factory ECU entirely and allows the end user (or your tuner) to continually retune the car by laptop or hand-held controller.

Power is Served!

And there you have it… the fundamentals to making more power – a tasty treat if there ever was one. Of course, just as the bigger cake isn’t always the healthiest meal if you overindulge and don’t exercise, more power for your car is not always the healthiest thing for it if you aren’t prepared to make some additional adjustments. At the top of your list, any time you add power, consider upgrading the brakes, at a minimum with quality pads, lines and fluid. After all, the faster you go, the more stopping power you’ll need. Next, if you drive a manual transmission car, consider a clutch upgrade (or a beefier torque converter if you have an automatic) to cope with the extra strain that the motor is exerting, along with some high performance engine mounts and suspension bushings to help keep unwanted gyrations at a minimum. Of course, for maximum enjoyment, you’ll definitely want to invest in a nice suspension to help your car tackle any curves that the road throws at you, and maybe even a nice set of wheels with sticky tires to help get the added power to the ground.
 
As you can see, the sky is the limit when it comes to performance modifications, but rather than feel pressured to do everything at once, if you opt instead to tackle these upgrades in manageable and workable chunks, you’ll find that you appreciate the merits of each set of upgrades more, and can satisfy your performance cravings for a lifetime.

K&N Filters, performance that sells itself.