What does the intake system do for your car?
The Intake system in any car is responsible for allowing the engine to breathe and helps your engine run cool. Why would you want to replace your stock intake system? It's a great DIY to get your hands dirty on your cobalt, it's a cheap easy mod that frees up some ponies, and it can improve your fuel economy as well.
--Your basic intake system (such as on our cars) includes--
1. The Intake
2. The Filter
3. The MAF Sensor (Mass Airflow Sensor) which we have or a MAP sensor (Mass Manifold Pressure Sensor).
4. The Throttle Body
5. The Intake Manifold
(*)SAI or Secondary Air Injection (On late 2006+ Cobalt L61 equipped)
The Intake
Why get an aftermarket intake system? Our stock airboxes are very restrictive. By allowing our engines to run cooler and breathe easier, we can FREE UP more power. It is important to note that an intake is not a power adder but a power free-er. There are also two types of intakes which are explained in this write-up: http://www.yourcobalt.com/forums/engine-mods/7885-starters-bolt-performance-mod-list.html
The Filter
There are two major types of filters. The first type offered by AEM is a dryflow filter meaning there is no additive oil. The problem with this oil is that it can effectively ruin the Mass Airflow Sensor. Of course many companies offer oiled filters with their systems such as K&N. The filter does just what it states: it filters the incoming air so we don't get any junk in the air in our combustion chamber. The stock filter is somewhat restrictive and doesn't let as much air into the intake piping as teh material that is used in aftermarket filters.
The MAF (Mass Airflow Sensor)
The MAF sensor senses the intake charge coming into the engine so the ECU (Engine Control Unit) knows how much fuel to deliver via the fuel injection system. The air mass coming into constantly changes from temperature (cold air is denser than warm air). Why is this important? If your ECU supplies too little or too much fuel, your performance is greatly effected and detonation can occur. That's why you MAF sensor is your friend.
The Throttle Body
The Throttle body allows the incoming air from the intake into the intake manifold via a butterfly valve. The butterfly valve is opened when the electronic throttle receives the signal that the gas has been pressed. Throttle body size can have an effect on throttle response, horsepower, and torque. The usual rule of thumb is a larger TB will yield better throttle response and higher horsepower because of the larger airflow. However, if you cannot tune for this and you increase your throttle body dimensions by a substantial amount, you can make your car run lean and possibly cause a fuel surge. A fuel surge is a surge of fuel from the ECU because the engine senses a lot more air so it delivers a large amount of fuel at once but sparactically. I'm not sure if our cars do this or not. It may throw the car into Limp mode because of running too lean meaning the car is at a reduced power level.
The Intake Manifold
What is the intake manifold? An intake manifold receives the air coming from the intake, through the butterfly valve of the throttle body, and evenly distributes the air into the ports in cylinder head via runners (true for port injection). There has been much debate on here about the 2.4L SS/NA manifold swap onto the 2.2L L61 motor. The major problem is that low end torque is decreased when longer, thinner runners of the SS manifold are sending the air charge to the ports. There is an increase in upper RPM horsepower and small increase in torque but a low end loss in torque is evident. That is why it is a better idea to get a free flowing exaust as well as a free flowing Intake system. Though this may sound like a lot, for roughly 800 dollars, you can gain approximately 20-25hp which isn't bad.
Here is the SS/NA manifold replacement kit for the 2.2L: Ecotec HO Intake Manifold Kit 2.2MMGF - Crate Engine Depot
The reason this changes the low end torque is because the incoming intake velocity is altered.
Secondary Air Injection
In Late model 2006 and up models of the L61 level cobalts, GM implemented a system called SAI or Secondary Air Injection. SAI is basically an emissions conrtol device and is basically a hose after the MAF and before the throttle body connection to the engine on a small port. Basically (from what I understand) air comes into the intake from the filter, up the intake piping and the SAI takes some of that air and pumps that to mix with the exaust fumes to affectively lower the emissions. It's important to note when buying an intake system if you have SAI or not.
I hope this sheds some light into why an intake system is so important. Again, a cooler engine is a happier engine! Happy modding.
The Intake system in any car is responsible for allowing the engine to breathe and helps your engine run cool. Why would you want to replace your stock intake system? It's a great DIY to get your hands dirty on your cobalt, it's a cheap easy mod that frees up some ponies, and it can improve your fuel economy as well.
--Your basic intake system (such as on our cars) includes--
1. The Intake
2. The Filter
3. The MAF Sensor (Mass Airflow Sensor) which we have or a MAP sensor (Mass Manifold Pressure Sensor).
4. The Throttle Body
5. The Intake Manifold
(*)SAI or Secondary Air Injection (On late 2006+ Cobalt L61 equipped)
The Intake
Why get an aftermarket intake system? Our stock airboxes are very restrictive. By allowing our engines to run cooler and breathe easier, we can FREE UP more power. It is important to note that an intake is not a power adder but a power free-er. There are also two types of intakes which are explained in this write-up: http://www.yourcobalt.com/forums/engine-mods/7885-starters-bolt-performance-mod-list.html
The Filter
There are two major types of filters. The first type offered by AEM is a dryflow filter meaning there is no additive oil. The problem with this oil is that it can effectively ruin the Mass Airflow Sensor. Of course many companies offer oiled filters with their systems such as K&N. The filter does just what it states: it filters the incoming air so we don't get any junk in the air in our combustion chamber. The stock filter is somewhat restrictive and doesn't let as much air into the intake piping as teh material that is used in aftermarket filters.
The MAF (Mass Airflow Sensor)
The MAF sensor senses the intake charge coming into the engine so the ECU (Engine Control Unit) knows how much fuel to deliver via the fuel injection system. The air mass coming into constantly changes from temperature (cold air is denser than warm air). Why is this important? If your ECU supplies too little or too much fuel, your performance is greatly effected and detonation can occur. That's why you MAF sensor is your friend.
The Throttle Body
The Throttle body allows the incoming air from the intake into the intake manifold via a butterfly valve. The butterfly valve is opened when the electronic throttle receives the signal that the gas has been pressed. Throttle body size can have an effect on throttle response, horsepower, and torque. The usual rule of thumb is a larger TB will yield better throttle response and higher horsepower because of the larger airflow. However, if you cannot tune for this and you increase your throttle body dimensions by a substantial amount, you can make your car run lean and possibly cause a fuel surge. A fuel surge is a surge of fuel from the ECU because the engine senses a lot more air so it delivers a large amount of fuel at once but sparactically. I'm not sure if our cars do this or not. It may throw the car into Limp mode because of running too lean meaning the car is at a reduced power level.
The Intake Manifold
What is the intake manifold? An intake manifold receives the air coming from the intake, through the butterfly valve of the throttle body, and evenly distributes the air into the ports in cylinder head via runners (true for port injection). There has been much debate on here about the 2.4L SS/NA manifold swap onto the 2.2L L61 motor. The major problem is that low end torque is decreased when longer, thinner runners of the SS manifold are sending the air charge to the ports. There is an increase in upper RPM horsepower and small increase in torque but a low end loss in torque is evident. That is why it is a better idea to get a free flowing exaust as well as a free flowing Intake system. Though this may sound like a lot, for roughly 800 dollars, you can gain approximately 20-25hp which isn't bad.
Here is the SS/NA manifold replacement kit for the 2.2L: Ecotec HO Intake Manifold Kit 2.2MMGF - Crate Engine Depot
The reason this changes the low end torque is because the incoming intake velocity is altered.
Secondary Air Injection
In Late model 2006 and up models of the L61 level cobalts, GM implemented a system called SAI or Secondary Air Injection. SAI is basically an emissions conrtol device and is basically a hose after the MAF and before the throttle body connection to the engine on a small port. Basically (from what I understand) air comes into the intake from the filter, up the intake piping and the SAI takes some of that air and pumps that to mix with the exaust fumes to affectively lower the emissions. It's important to note when buying an intake system if you have SAI or not.
I hope this sheds some light into why an intake system is so important. Again, a cooler engine is a happier engine! Happy modding.
