Volvo 940 Turbo Tuning – Cheaply get more power from a B230

A brief introduction to the Volvo B230 turbo engine

The Volvo B230 engine is also known as a “Red Block,” as the name might suggest it owes this to its color. Volvo’s B230 (B230FK and B230FT) engine is an 8-valve 2.3L turbocharged engine that delivers 135hp (B230FK LPT) or 165hp (B230FT HPT) of power as standard.

The difference between the B230FK and the B230FT is in the wastegate actuator also called the pressure box. This ensures that the B230FK turbo gives a maximum pressure of about 0.35 bar and the B230FT gives 0.6 bar of turbo pressure. The engines are otherwise completely identical to each other.

Getting more power from the Volvo 940 B230 turbocharger

Before power can be extracted from the Volvo 940 B230 turbo it is important to have a good foundation. You do this by giving your Volvo 940 with B230FK/FT engine a so-called Stage 0 turn/tune-up.

Volvo 940 B230 Stage 0 Tune-Up

With a stage 0 tune-up, you perform major maintenance on the engine and peripheral components that will wear harder with more power. Another reason for a stage 0 tune-up is that you have a good zero point of the engine. Therefore, replace the following items: engine oil, spark plugs, air filter, transmission oil and any other items that break down more often on a Volvo 940. These include the ignition module that sits against the side screen, the fuel relay which sometimes fails or the crankshaft position sensor.

After the stage 0 tune-up or simply put; major maintenance, the Volvo 940 is ready for more power.

Volvo 940 B230 FK/FT – 175HP Boost controller + Turbo pressure gauge (Budget €100.00)

As stated earlier, the B230FK and B230FT are identical to each other except for the turbo pressure box. The way the B230FT generates more power is to pump more air (0.6 bar instead of 0.35 bar) into the cylinder chamber while injecting more fuel. Knowing this, then, you can say that a 135HP B230FK engine can also be lifted to the 165HP; and that is true. The standard ECU (Engine Control Unit), or control of the injection and fuel system, can come along at up to about 0.7 bar of turbo pressure. Above that, under heavy load, too lean a mixture can be injected which can cause damage to the engine by excessive heat and potentially detonation. Detonation is the premature ignition of a mixture without a spark plug.

Increasing the turbo pressure on a Volvo 940 with a B230 engine is very simple. This can be done with a manual boost controller also called a manual boost controller. This little device causes the air (turbo pressure) going to the pressure box to leak away slightly, causing the pressure box to work only at a higher pressure.

Brief explanation pressure box/wastegate:

A turbo gets its drive from the exhaust gases leaving the engine. These gases pass through the turbine housing which spools up the turbocharger, creating overpressure in the compressor housing. If the turbo turns harder due to more exhaust gas passing the turbine wheel, in the turbine housing, then more turbo pressure (overpressure) will also be created. To ensure that this pressure stays within the margins, turbocharger manufacturers have built in valves (wastegates). This valve ensures that exhaust gases no longer pass through the turbine housing but are discharged directly into the exhaust. As a result, the turbo slows down.

Controlling the valve is done with a wastegate actuator, in the Netherlands this is often called the pressure box. From a certain turbo pressure, a rod pushes the valve further and further open until it is maximally open and much of the exhaust gases go directly into the exhaust and thus “brake” the turbo.

Mounting a Boost Controller and Turbo Pressure Gauge – Increase Turbo Pressure

Mounting a boost controller on a Volvo 740/940 is relatively easy and will take about 30 minutes. As stated earlier, with the original Volvo 740 and Volvo 940 ECU, there is a limit to the turbo pressure. To stay under this limit, a turbo pressure gauge will also need to be connected, this way it is possible to read exactly what the turbo pressure is and the boost controller can be set correctly.

Below is an image showing how to connect the boost controller.

Originally a hose goes from the compressor housing on the turbo directly to the wastegate actuator or pressure box. This hose should be disconnected so that a tee piece can be put between it (tee piece). This tee goes back to the pressure box and to the boost controller. The boost controller has a set screw that controls how much pressure will leak out and thus determines how much turbo pressure will be created because the pressure box opens later and thus less exhaust gas “leaks out.

Adjusting the boost controller

Each boost controller comes with an instruction manual detailing how to adjust it. The operation is generally the same; turning the knob all the way in is original turbo pressure, all the way out is maximum turbo pressure. To start, it is wise to turn the boost controller all the way in and then 1 turn loose. Then go for a drive so that the engine can reach operating temperature. Once it is up to temperature you can accelerate at full throttle and at the same time look at the turbo pressure gauge, the turbo should now deliver more pressure than original but not yet the desired pressure of 0.7 bar.

Turn the adjusting screw ever so slightly further and make a test drive until the turbo pressure gauge reads about 0.7 bar. With this turbo pressure, the Volvo B230 engine will feel significantly faster and also produce more power than when it came from the factory.

More power and more turbo pressure!

The installation is complete and you can start enjoying the beneficial extra power your Volvo 740/940 will now provide.

Keep in mind that the more power required of the engine the more important maintenance will become. Therefore, always give the Volvo a timely service so that it can be driven for a long time to come.

Disclaimer:

LucaCarMods cannot be held liable nor is it responsible for any damages caused by performing this modification.