Revision history for Forced-Induction
Additions:
Turbocharging
In internal combustion engines, a turbocharger is a forced-induction compressor powered by the engine's exhaust gas. The purpose of a turbocharger is to increase the mass of air entering the engine to create more power.
A turbocharger consists of a turbine and a compressor linked by a shared axle. The turbine inlet receives exhaust gases from the engine causing the turbine wheel to rotate. This rotation drives the compressor, compressing ambient air and delivering it to the air intake manifold of the engine at higher pressure, resulting in a greater amount of the air entering the cylinder. In some instances, compressed air is routed through an intercooler before introduction to the intake manifold.
How-To: Install a Turbocharger Setup
1 Components
1.1 Turbocharger
1.2 Wastegate
1.3 Turbo Manifold
1.4 Downpipe/Flange
1.5 Braided Oil Lines
1.6 Charge Piping
1.7 Blow-off Valve
1.8 Fuel Injectors
1.9 Boost Controller
1.10 Intercooler
1.11 2 Bar MAP Sensor
1.12 Intake Manifold Gasket
1.13 Spark Plugs
1.14 Tuning
Components
The main components of a turbocharger system are as follows:
Turbocharger
A turbocharger is a gas compressor used for forced-induction of an internal combustion engine. Like a supercharger, the purpose of a turbocharger is to increase the density of air entering the engine to create more power. A turbocharger consists of a turbine and a compressor on a shared shaft. The turbine section of a turbocharger is a heat engine in itself. It converts the heat energy from the exhaust to power, which then drives the compressor, compressing ambient air and delivering it to the air intake manifold of the engine at higher pressure, resulting in a greater mass of air entering each cylinder. In some instances, compressed air is routed through an intercooler before introduction to the intake manifold. Because a turbocharger is a heat engine, and is converting otherwise wasted exhaust heat to power, it compresses the inlet air to the engine more efficiently than a supercharger.
More information, including diagrams, can be found on www.howstuffworks.com
Wastegate
A wastegate is a valve that diverts exhaust gases away from the turbine wheel in a turbocharged engine system. Diversion of exhaust gases regulates the turbine speed, which in turn regulates the rotating speed of the compressor. The primary function of the wastegate is to regulate the maximum boost pressure in turbocharger systems, to protect the engine and the turbocharger.
Turbo Manifold
There are two main types of exhaust manifolds available, a top mount log manifold designed by Street Track Racing (STR), which can be found on eBay, or a straight out manifold which mounts the turbocharger straight back in the engine bay out of plain sight. The latter of the two can be found on Vulcan Turbo and TurboTechRacing.
Downpipe/Flange
The downpipe is simply the exhaust pipe that connects to the turbine's outlet, and connects to the rest of the exhaust system (typically at the flexpipe and/or catalytic converter just under the firewall). It is suggested that one use a v-band exhaust housing on the turbocharger, as v-band clamped exhaust components are easy to install/uninstall, and seal extremely well.
Braided Oil Lines
The oil feed and return hoses should be braided stainless steel for maximum reliability and damage resistance. An oil feed line is typically tapped off of the oil pressure sensor's socket in between the camshaft towers just to the right of the IDI cover. The thread size is 1/4" NPT. One can either get an appropriate sized brass tee to use the stock oil sensor, or bypass it completely. The oil drain line requires drilling and tapping of the aluminum oil pan, or welding an aluminum bung to the oil pan where a hole is drilled.
Charge Piping
Charge piping is perhaps the easiest material to come by for turbocharged applications. Found commonly on eBay and all reputable turbocharging application websites, one is given the option of size, ranging anywhere from 2'' to 4'' in some cases, shape, and color. There are no "kits" made for the Alero, so one must obtain the bends they need and either couple them with silicone and t-bolt clamps or weld.
www.siliconeintakes.com is one excellent source for high quality silicone couplers and other various turbocharging related components.
Blow-off Valve
The blow off valve is the most well known part of a turbocharging application, besides the turbo itself. The blow off valve is responsible for diverting the charged air into the atmosphere when the throttle body closes while under boost. Without this device, charged air is forced against the impeller of the turbocharger, threatening the strength and longevity of the turbo.
Fuel Injectors
When adding more air to an engine, one must have the capability to add more fuel. The stock injectors are NOT adequate for any type of boosted application. Injector sizing depends on what power range you're shooting for. One can utilize the 310cc injectors that come with the GM Supercharger Kit, however those will only suffice for low boost applications. Injector usage and location information can be found in LD9 2.4L Twin Cam > Fuel System.
Boost Controller
Boost controllers are exactly that. They control the amount of boost pressure in the system by limiting the amount of pressure the wastegate sees. These come in both manual and electronic, ranging from very cheap to somewhat pricey depending on brand and features. The most basic boost controller vents some of the pressurized air, preventing the wastegate from closing until a higher boost level. These are typically regarded as a poor design and are a way of having a controlled boost leak in the system, which is not the most efficent way of doing things.
The most common style of manual boost controller uses a ball and spring. By compressing the spring using a threaded thumbscrew on top of the unit, the ball valve becomes more resistant to pressure seeping through to the wastegate.
Intercooler
An intercooler, or charge air cooler, is an air-to-air or air-to-liquid heat exchange device used on turbocharged engines to improve their volumetric efficiency by increasing intake air charge density through isochoric cooling. A decrease in air intake temperature provides a denser intake charge to the engine and allows more air and fuel to be combusted per engine cycle, increasing the output of the engine and greatly reducing the possibility of detonation (pre-ignition).
This is an optional device (for applications under 6 PSI), but is still HIGHLY recommended, as the power and cooling that results in their usage is immense.
2 Bar MAP Sensor
A two bar manifold absolute pressure sensor is required to utilize the GM Supercharger Reflash and to allow the vehicle to read positive pressure (0-14.7 psi). The stock 1 bar MAP sensor reads "negative" 14.7 psi up to 0 psi, which is only vacuum. When boosting, the car must be able to read the positive (0-14.7 psi) pressure as well, so a 2 bar MAP sensor is used. A 2.5 or even 3 bar MAP sensor could be used, but requires a custom standalone system for tuning, as the HPTuners-editable GM Supercharger reflash can only use a 2 bar sensor.
A Duralast sensor, part number #SU1285 from AutoZone, can be used as the new 2 bar MAP sensor, pictured right.
Intake Manifold Gasket
This gasket goes between the intake manifold and head in order to block off the small PCV hole between ports 2 and 3. It is vital to oil system integrity that this be blocked off, and then the PCV system modified as described in the How-To. You can purchase this gasket by request through Overkill Engineering Motorsports.
Spark Plugs
In order to safely boost an engine, colder heat range spark plugs are required. These are an extra safeguard from detonation (combustion gases igniting before the spark fires, which will lead to significant engine damage).
NGK TR6 are the typical model used in LD9 boosted engines.
Tuning is essential to any forced induction system. For this engine, HPTuners it he ideal (if not only) tuning software to use. When using a 2 bar MAP sensor, one must get the GM Supercharger Reflash from a GM Performance Parts Dealer or through someone who has HPTuners and the GM tune already. It provides a decent baseline to use for your turbocharged setup.
Many things can be adversely affected and catastrophic failure can result by tuning with little knowledge of the subject and the methods of doing it.
If you plan on tuning your own vehicle, it is HIGHLY suggested that you research heavily in the J-Body Organization's Tuning forum.
In internal combustion engines, a turbocharger is a forced-induction compressor powered by the engine's exhaust gas. The purpose of a turbocharger is to increase the mass of air entering the engine to create more power.
A turbocharger consists of a turbine and a compressor linked by a shared axle. The turbine inlet receives exhaust gases from the engine causing the turbine wheel to rotate. This rotation drives the compressor, compressing ambient air and delivering it to the air intake manifold of the engine at higher pressure, resulting in a greater amount of the air entering the cylinder. In some instances, compressed air is routed through an intercooler before introduction to the intake manifold.
How-To: Install a Turbocharger Setup
1 Components
1.1 Turbocharger
1.2 Wastegate
1.3 Turbo Manifold
1.4 Downpipe/Flange
1.5 Braided Oil Lines
1.6 Charge Piping
1.7 Blow-off Valve
1.8 Fuel Injectors
1.9 Boost Controller
1.10 Intercooler
1.11 2 Bar MAP Sensor
1.12 Intake Manifold Gasket
1.13 Spark Plugs
1.14 Tuning
Components
The main components of a turbocharger system are as follows:
Turbocharger
A turbocharger is a gas compressor used for forced-induction of an internal combustion engine. Like a supercharger, the purpose of a turbocharger is to increase the density of air entering the engine to create more power. A turbocharger consists of a turbine and a compressor on a shared shaft. The turbine section of a turbocharger is a heat engine in itself. It converts the heat energy from the exhaust to power, which then drives the compressor, compressing ambient air and delivering it to the air intake manifold of the engine at higher pressure, resulting in a greater mass of air entering each cylinder. In some instances, compressed air is routed through an intercooler before introduction to the intake manifold. Because a turbocharger is a heat engine, and is converting otherwise wasted exhaust heat to power, it compresses the inlet air to the engine more efficiently than a supercharger.
More information, including diagrams, can be found on www.howstuffworks.com
Wastegate
A wastegate is a valve that diverts exhaust gases away from the turbine wheel in a turbocharged engine system. Diversion of exhaust gases regulates the turbine speed, which in turn regulates the rotating speed of the compressor. The primary function of the wastegate is to regulate the maximum boost pressure in turbocharger systems, to protect the engine and the turbocharger.
Turbo Manifold
There are two main types of exhaust manifolds available, a top mount log manifold designed by Street Track Racing (STR), which can be found on eBay, or a straight out manifold which mounts the turbocharger straight back in the engine bay out of plain sight. The latter of the two can be found on Vulcan Turbo and TurboTechRacing.
Downpipe/Flange
The downpipe is simply the exhaust pipe that connects to the turbine's outlet, and connects to the rest of the exhaust system (typically at the flexpipe and/or catalytic converter just under the firewall). It is suggested that one use a v-band exhaust housing on the turbocharger, as v-band clamped exhaust components are easy to install/uninstall, and seal extremely well.
Braided Oil Lines
The oil feed and return hoses should be braided stainless steel for maximum reliability and damage resistance. An oil feed line is typically tapped off of the oil pressure sensor's socket in between the camshaft towers just to the right of the IDI cover. The thread size is 1/4" NPT. One can either get an appropriate sized brass tee to use the stock oil sensor, or bypass it completely. The oil drain line requires drilling and tapping of the aluminum oil pan, or welding an aluminum bung to the oil pan where a hole is drilled.
Charge Piping
Charge piping is perhaps the easiest material to come by for turbocharged applications. Found commonly on eBay and all reputable turbocharging application websites, one is given the option of size, ranging anywhere from 2'' to 4'' in some cases, shape, and color. There are no "kits" made for the Alero, so one must obtain the bends they need and either couple them with silicone and t-bolt clamps or weld.
www.siliconeintakes.com is one excellent source for high quality silicone couplers and other various turbocharging related components.
Blow-off Valve
The blow off valve is the most well known part of a turbocharging application, besides the turbo itself. The blow off valve is responsible for diverting the charged air into the atmosphere when the throttle body closes while under boost. Without this device, charged air is forced against the impeller of the turbocharger, threatening the strength and longevity of the turbo.
Fuel Injectors
When adding more air to an engine, one must have the capability to add more fuel. The stock injectors are NOT adequate for any type of boosted application. Injector sizing depends on what power range you're shooting for. One can utilize the 310cc injectors that come with the GM Supercharger Kit, however those will only suffice for low boost applications. Injector usage and location information can be found in LD9 2.4L Twin Cam > Fuel System.
Boost Controller
Boost controllers are exactly that. They control the amount of boost pressure in the system by limiting the amount of pressure the wastegate sees. These come in both manual and electronic, ranging from very cheap to somewhat pricey depending on brand and features. The most basic boost controller vents some of the pressurized air, preventing the wastegate from closing until a higher boost level. These are typically regarded as a poor design and are a way of having a controlled boost leak in the system, which is not the most efficent way of doing things.
The most common style of manual boost controller uses a ball and spring. By compressing the spring using a threaded thumbscrew on top of the unit, the ball valve becomes more resistant to pressure seeping through to the wastegate.
Intercooler
An intercooler, or charge air cooler, is an air-to-air or air-to-liquid heat exchange device used on turbocharged engines to improve their volumetric efficiency by increasing intake air charge density through isochoric cooling. A decrease in air intake temperature provides a denser intake charge to the engine and allows more air and fuel to be combusted per engine cycle, increasing the output of the engine and greatly reducing the possibility of detonation (pre-ignition).
This is an optional device (for applications under 6 PSI), but is still HIGHLY recommended, as the power and cooling that results in their usage is immense.
2 Bar MAP Sensor
A two bar manifold absolute pressure sensor is required to utilize the GM Supercharger Reflash and to allow the vehicle to read positive pressure (0-14.7 psi). The stock 1 bar MAP sensor reads "negative" 14.7 psi up to 0 psi, which is only vacuum. When boosting, the car must be able to read the positive (0-14.7 psi) pressure as well, so a 2 bar MAP sensor is used. A 2.5 or even 3 bar MAP sensor could be used, but requires a custom standalone system for tuning, as the HPTuners-editable GM Supercharger reflash can only use a 2 bar sensor.
A Duralast sensor, part number #SU1285 from AutoZone, can be used as the new 2 bar MAP sensor, pictured right.
Intake Manifold Gasket
This gasket goes between the intake manifold and head in order to block off the small PCV hole between ports 2 and 3. It is vital to oil system integrity that this be blocked off, and then the PCV system modified as described in the How-To. You can purchase this gasket by request through Overkill Engineering Motorsports.
Spark Plugs
In order to safely boost an engine, colder heat range spark plugs are required. These are an extra safeguard from detonation (combustion gases igniting before the spark fires, which will lead to significant engine damage).
NGK TR6 are the typical model used in LD9 boosted engines.
Tuning is essential to any forced induction system. For this engine, HPTuners it he ideal (if not only) tuning software to use. When using a 2 bar MAP sensor, one must get the GM Supercharger Reflash from a GM Performance Parts Dealer or through someone who has HPTuners and the GM tune already. It provides a decent baseline to use for your turbocharged setup.
Many things can be adversely affected and catastrophic failure can result by tuning with little knowledge of the subject and the methods of doing it.
If you plan on tuning your own vehicle, it is HIGHLY suggested that you research heavily in the J-Body Organization's Tuning forum.
