With all of the aftermarket products out there on the market, there may be some confusion as to how all of them work.

In my short series of articles, I plan to cover the technical side of how basic aftermarket upgrades benefit your car, and explain the important question: “Why do I need that, and what does it do?”

In this article I will explain the functions of Cold Air Intake systems, but in upcoming articles I will be covering Exhaust Systems, Ignition, and Forced Induction.

“What is wrong with the factory intake that is on my car?” 

Due to consumer demands placed on auto manufacturers from car buyers like yourself, the manufacturers strive to produce cars that are quieter than their competition. The average consumer of any automobile wants a smooth quiet ride in their car, and does not want to deal with the excessive noise of a high performance engine. Because of this, most entry level cars have very restrictive intakes from the factory. These factory intake systems may consist of bulky sound bafflers that connect to the intake system to trap air and slow it down, while others may appear to have less obvious features that negatively affect performance. This reduces the rumbling or droning noises created by the engine, and makes for a quieter ride for you and those on the road with you.

These other features typically include seemingly harmless ridged areas to allow for flexibility in the intake system, but in actuality these ridged areas create a turbulence in the airflow coming into the engine and slow down the flow of air entering your engine. Another area that could be improved are pinched bends within the intake system, this reduction in diameter will force air to congest in this area resulting in a restriction on air volume entering the engine. As you may have guessed by now, reduced volume and velocity result in a quieter engine, but at the cost of some performance. This does not mean that the engineers at the factory are not capable of making a high performance system, rather they just have more factors to consider when making a well designed car.

Let’s face it, the manufacturer of your car placed the factory air intake in that location for a reason. In some cases that location may not have performance in mind, but in most cases the location they select is still the optimal place to have your air filter. After all, that location could be the place that received the most airflow in the engine bay, it may be away from the extreme temperatures of the exhaust system, or it might be properly protected from road water which could cause damage to your engine. Chances are that the aftermarket companies will use a location very similar to the original equipment, but they will introduce other features to the intake that will make improvements on the original design.

If you find yourself buying an intake that changes the location of your air filter, or in particular one that places it much closer to the road be aware that you may be putting yourself in harms way. By locating the air filter closer to the ground, or within fender wells, the idea is to draw air from a location that has a cooler ambient temperature. The one major drawback to this is that your air filter has now been exposed to more risk for sucking in water rather than air, which can damage electrical sensors or even hydro-lock your motor causing engine failure. Some manufacturers will give you a warning on the product that may include labels such as “For Off-road use only”, or “For Dry Weather Only”. If you receive such warning with your intake system be very cautious about driving in wet weather conditions, even if the roads are wet and it has stopped raining. Do a little research before purchasing your Cold Air Intake and make sure that you are not buying a potentially harmful unit if you feel uncomfortable about exposing your engine to the elements.

When looking for a high quality intake, it is important that you first buy one with a high quality air filter. The air filter should be a brand that you recognize, and should feature an oiled element. The reason for the oil on the element is to trap the smaller dust particles that would normally pass through the gauze that the filter is made out of. Your stock unit was made out of paper, but it was also well protected from the road dust since it was contained within that bulky plastic housing. That original housing kept most of the atmospheric dust from getting to the air filter, thus there was no need for it to be oiled. On the downside, that housing restricted the amount of air that your filter was exposed to, resulting in less scavenging for air and less power. These oiled air filters can typically be serviced every few oil changes instead of being thrown away, so there should be no need to purchase additional air filters in the future. Instead, most companies will make a Filter Service Kit that you can purchase for around $12 that will allow you to clean and re-oil the filter throughout its entire service life.

The reason it is important to make sure your kit contains a high quality filter when using oiled filters is because any residual oil on the filter could harm your sensors. Most reputable companies know what they are doing when making these air filters, and purchasing a quality brand should ensure that you are buying a properly prepared filter right from the box.

If the filter is over-oiled, that excess oil will get drawn through intake system and coat the sensitive components of the Mass Airflow Sensor and Intake Air Temperature Sensor. If this oil coats the Mass Airflow Sensor, then your cars computer will receive inaccurate readings on the amount of air coming through the intake, and your computer will not be able to provide enough fuel for your car to run safely and properly. If you notice you engine behaving poorly after installing a new cold air intake, or after servicing your air filter, this oil is likely the cause.

 If your check engine light comes on as a result of this you should take action immediately. Fixing this problem is relatively simple, but easily avoidable. You will need to remove your Mass Airflow Sensor and clean it carefully with Electrical Parts Cleaner, and then re-install it facing the proper direction. You will also need to remove your air filter, and clean it with soap and water thoroughly and then reapply the filter oil in a much less generous manner as you did before. A little bit of oil goes a long way.

When examining the Cold Air Intake, you should look to see what materials it is made out of, and determine if the company who manufactured it is one that you recognize. The importance of purchasing a well recognized brand has nothing to do with “being cool”, but has everything to do with how well it is going to fit the first time, and how much it will benefit your car. The experience of the well-known companies pays off when it comes to insuring a proper fit, and durable materials. After all, you only want to install this intake once, right?

Other things to look for are the materials being used. If there are any bends in the intake system carefully examine how they are being addressed. If the bends are made out of angular couplers or “elbows” these are perfectly acceptable. These couplers will normally allow for smooth airflow around corners, but still provide the flexibility that is required by the intake system as the motor operates. These elbows are typically used in the areas where there was pinched tubing or ridged rubber areas on the stock intake. These help reduce turbulence in the intake system. If the bends are being made out of metal or plastic tubing, then carefully examine that those are mandrel bends which maintain the original inner diameter throughout the entire bend. Avoid systems that are made by crush-bending, which will cause bottlenecks in the airflow and slow down the movement of air through your system.

If you noticed, the original equipment on your car was probably made from plastic. Plastic is a preferable material for aftermarket intakes as well, but you will notice that not many companies use plastic, and instead opt for metal and rubber components. There are many reasons why plastic is preferable, the most prevalent in regards to performance is how they do or don’t retain engine heat. Plastic has much less of a tendency to retain heat from the engine compartment, and is less susceptible to “heat soak”. By reducing the amount of heat your Cold Air Intake is exposed to, you will create a cooler and more dense air charge in the cylinder. The more dense/cool the air is, the more power your car will make. The other reason plastic is a preferable material is that plastic is not as vulnerable to corrosion as metal intakes are. If you find yourself buying a metal intake , as is commonly the case, try to buy one that is coated or painted to prevent the metal from deteriorating.

The reason most aftermarket manufacturers use metal as a material in their product is because plastic molding is a very expensive process. It is much easier for a small company to purchase metal tubing and then cut it to predetermined lengths, and then use readily available couplers to hold the piece together. It is not practical for most companies to invest in expensive plastic molding equipment to produce intake systems that they are going to sell a very limited number of to begin with. The metal units are cheaper to produce, and as a result will typically cost far less than any available plastic counterpart. In the long run you will be better off buying plastic if it is available, but you will be the ultimate judge in determining whether it is worth the extra money.

This answer is both “Yes” and “No”. Your car delivers fuel to the cylinders based upon the readings from your engine sensors. Provided that your engine’s sensors are functioning properly, most cars will not need recalibration to operate within specifications.

On the other hand, your engine’s computer is limited in how much it can adjust for changes to the original set-up. Most cars are able to adjust for approximately 13% change in operating conditions before an unfavorable condition occurs. Anything beyond that percentage and your car will struggle to keep up with the changes, and may throw a check engine light. If you find yourself throwing a check engine light after installing an intake, first try checking and cleaning your Mass Airflow Sensor and Air Filter as previously mentioned. Then unplug the cars battery for at least a half an hour to reset the check engine light. If the problem reoccurs, then custom tuning may be required, though it is rare with just basic modifications.

If you are looking to get the most out of your cars new intake, custom tuning will still benefit you. By recalibrating the engines configuration to accommodate for the change in airflow and intake temperatures you will get a more accurate air fuel ratio. This more accurate calibration will enhance the benefits that your cold air intake provides, and result in smoother engine response and even more horsepower than just the intake alone.

In general cold air intakes will provide up to 5% additional horsepower to any given motor. But more specifically for the Pontiac Solstice and Saturn Sky you can expect gains of approximately 3% peak horsepower. This lower number does not mean that the Ecotec is not responsive to modifications, but is rather a testament to how well designed the original intake was for the car. Since the Solstice and Sky were designed by GM Performance Division, more performance minded engineering went into designing the original layout of the intake, exhaust, and suspension components.

When you break down what 3% equates to in horsepower it is roughly equal to 5 horsepower. This number may seem low to you, but this is a more realistic number than what most manufacturers will tell you. When a manufacturer claims horsepower, they may not always reference peak horsepower, which is the maximum number that your engine produces, they may be claiming horsepower that is “under the curve” or in other words, at lower RPM ranges. Since there are no laws governing what a company claims or how they are required to measure it, you will often see inflated numbers from the parts manufacturers to get you more excited about their product. In reality you should take any manufacturers estimates with a grain of salt, and not assume that you are guaranteed any actual amount of horsepower. When it comes down to it, if you are happy with the performance that the product delivers and how it looks or sounds then that is all that really matters.