Turbo 101

The following document contains information on how a turbo works and a list of components and their usage on the Ford 2.3l turbo motor.

 

What is a Turbo:

A Turbo is a forced induction device used on many production diesel and gasoline engines. A turbo uses hot expelled exhaust gasses to spin a turbine connected to an air compressor pump which intern forces compressed air into the engine. Because more air is being forced into the engine you must also increase the fuel to prevent detonation or a lean condition. Adding more fuel and air increases the horsepower output of the engine. The turbo is located in various locations depending on the engine but most turbo chargers found on production cars will be connected directly to the exhaust manifold. A turbo can be used in conjunction with another turbo which is referred to as a Twin-Turbo system. Most Twin-Turbo systems are designed to be used on V6 or V8 engines.

What is the Vane Air Meter (VAM):

The Vane Air Meter measures the temperature and the amount of air entering the motor. It is located on the passenger side fender under the air filter unit. There are two types of VAM meters, the Small VAM and the Large VAM. The large VAM can be found on all SVO’s and 87-88 Turbo Coupes. The Small VAM is pictured on the left.

What is the Throttle Position Sensor (TPS):

The Throttle Position Sensor is located on the throttle body and allows the computer to read the position of the throttle blade and adjust accordingly.

What is the Idle Air Control Sensor (IAC):

The Idle Air Control it is located on the throttle body just above the TPS and helps control the idle speed.

What is the Air Charge Temperature Sensor (ACT):

The Air-Charge Temperature measures the air coming into the intake after the turbo so the computer can correctly alter the timing. It is located in the lower intake manifold facing the firewall. It is the lower of 2 sensors found in that area.

What is the Knock Sensor:

The Knock Sensor allows your computer to hear detonation in the engine and retard the timing accordingly. It is located in the lower intake manifold facing the firewall just above the ACT sensor. It is the upper of top sensors found in that area. This sensor is commonly unplugged as it to prevent
unnecessary retarding of the timing due to false detection of detonation.

What is the Oxygen Sensor (02):

The Oxygen sensor is used to sense the presence of oxygen in the exhaust gas and signal the computer, which can reference the voltage signal to an air/fuel ratio. It is located on the elbow of the exhaust system which connects the turbo to the down pipe.

What is the Fuel Pressure Regulator (FPR):

The Fuel Pressure Regulator helps keep a constant and adequate pressure level of fuel to the engine. It is located between the upper and lower intake manifold at the end of the fuel rail.

What is the Boost Control Switch (BCS):

The Boost Control Switch or Valve is used to control the amount of boost the turbo will produce. It accomplishes this by measuring the boost level and then electronically opens or closes the boost valve. As the valve opens it allows air to escape through the waste-gate thus reducing and limiting the boost pressure. If the valve closes the boost will rise to the stock setting of 10psi and then open the waste-gate thus limiting the boost
level. It is located on the passenger inner fender next to the BAP.

What is the Waste-gate:

The waste-gate is a valve that allows air to bypass the Turbo exhaust turbine thus reducing the amount of boost the turbo will make. It is controlled by the BCS. The waste-gate is located at the rear of the exhaust side of the turbo before the down-pipe.

What is the Manifold Absolute Pressure Sensor (MAP):

The Manifold Absolute Pressure sensor allows the computer to make corrections to the fuel and timing tables based on different altitudes. It is located on the passenger inner fender.

What is the Barametric Absolute Pressure Sensor (BAP):

Also know as BPS or BAP is a derivative of MAP. The Barametric Absolute Pressure Sensor allows the computer to make corrections to the fuel and timing tables based on different altitudes. It is located on the passenger inner fender next to the BCS.

What is the Positive Crankcase Ventilation Valve (PCV):

The Positive Crankcase Ventilation Valve is part of the positive crankcase ventilation system. It is located on the driver’s side of the motor behind the alternator.

What is the Exhaust Gas Recirculation Valve (EGR):

The Exhaust Gas Recirculation Valve allows gases from the exhaust to recirculation back though the intake and be re-burned in the combustion process. It is attached to the throttle body near the TPS. There is a tube that runs from the back of the exhaust manifold around the back of the
engine and to the EGR.

What is a Fuel Injector:

The fuel injector is a low impedance device that injects gas into the manifold. The injectors are located on the fuel rail on the lower intake manifold. The color of the top of the injector dictates which injector it is.

What is a Inline-4 Intake:

The Inline-4 intake manifold is a pre 85.5 production manifold featuring small inline runners. It is located on the driver side of the cylinder head.

What is the 4-Square Intake:

The 4-Square intake manifold is a post 85.5 production manifold and feature slightly larger runners than pre 85.5 manifolds and are arranged in a square pattern as compared to the 4-Inline manifold. It is located on the driver’s side of the cylinder head.

What is a IHI Turbo:

The IHI Turbo is oil and water cooled and used on all 1987 and 1988 Turbo Coupes. It is located on the passenger side of the motor and is
bolted to the Exhaust manifold.

What is a T3, T3/T4 and T04E Turbo:

The T3, T3/T4 and TO4E turbo chargers are oil cooled and/or water cooled. They are larger than the stock IHI turbo used on the Turbo Coupe
and a recommended upgrade over the small IHI turbo.

What is a Compressor Map:

A Compressor Map tells the efficiency at which a turbo operates given a pressure ratio and the air flow requirements of the engine. A compressor map is used to determine the proper turbo selection for a given engine.

What is a Blow-Off Valve (BOV):

The Blow-Off Valve is a device used to release excess turbo pressure once the throttle blade has closed. It is located just before the throttle body after the intercooler. There are two types of Blow Off valves, one that vents air into the atmosphere and one that releases it back into the intake track.

What is a Intercooler (IC):

The intercooler is a device resembling a radiator but with larger passages that the turbo pumps air through to lower the air temperature. It is located in several places. On the Turbo Coupe it is located on top of the IHI Turbo compressor housing. After market intercoolers are usually mounted in front of the radiator.

What is the E3 Exhaust Manifold:

The E3 is a pre1985 production exhaust manifold for the IHI/T3 Turbo motors. It is located on the passenger side of the cylinder head.

What is the E6 Exhaust Manifold:

The E6 is a post 1985 production exhaust manifold for the T3 Turbo motors. It is located on the passenger side of the cylinder head.

What is the Electronic Engine Control Processor (EEC):

The Electronic Engine Control processor is the brain of the engine. It controls fuel and timing management functions. It is located inside the vehicle just behind the passenger kick panel. The LA3 production turbo computer is the most sought after for its better fuel and timing curves.

What is the Air Filter:

The air filter filters dirt and other particles out of the air entering the motor. It is located in the front passenger side of the engine bay mounted to the top of the VAM. You can use the 6” K&N filter “RE-0930” as a direct bolt on replacement for the stock air cleaner housing and filter.

What is the Fuel Pump (FP):

The fuel pump supplies fuel to the fuel injectors. It is located inside the gas tank. It is recommended that the pump be upgraded to a 190 to 255lb pump for any boost levels above 15psi.