Volvo 940 Turbo Tuning – Affordably getting 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', and as the name suggests, it owes this to its color. The B230 (B230FK and B230FT) engine from Volvo is an 8-valve 2.3L turbo engine that delivers 135hp (B230FK LPT) or 165hp (B230FT HPT) as standard.
The difference between the B230FK and the B230FT lies in the wastegate actuator, also known as the pressure capsule. This ensures that the B230FK turbo delivers a maximum pressure of approximately 0.35 bar and the B230FT delivers 0.6 bar turbo pressure. The engines are otherwise completely identical.
Getting more power out of the Volvo 940 B230 turbo
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 service/tune-up.
Volvo 940 B230 Stage 0 Tune-Up
During a stage 0 tune-up, you perform major maintenance on the engine and peripheral components that will wear out faster with increased power. Another reason for a stage 0 tune-up is that you have a good baseline for the engine. Therefore, replace the following: engine oil, spark plugs, air filter, transmission oil, and possibly other items that are more prone to failure on a Volvo 940. This includes the ignition module located against the side panel, the fuel relay which can sometimes fail, 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 previously mentioned, the B230FK and B230FT are identical except for the turbo's pressure capsule. The way the B230FT generates more power is by pumping more air (0.6 bar instead of 0.35 bar) into the cylinder chamber and simultaneously injecting more fuel. Knowing this, you can conclude that a 135HP B230FK engine can also be boosted to 165hp; and that's correct. The standard ECU (Engine Control Unit), which controls the injection and fuel system, can handle turbo pressure up to approximately 0.7 bar. Above this, under heavy load, an overly lean mixture may be injected, which can cause engine damage due to excessive heat and potential detonation. Detonation is the premature ignition of a mixture without the involvement of 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. This device causes the air (turbo pressure) going to the pressure capsule to leak slightly, which means the pressure capsule only starts working at a higher pressure.
Brief explanation of pressure capsule/wastegate:
A turbo is driven by the exhaust gases leaving the engine. These gases pass through the turbine housing, which spools up the turbo, creating overpressure in the compressor housing. If the turbo spins faster due to more exhaust gases passing through the turbine wheel in the turbine housing, more turbo pressure (overpressure) will also be generated. To ensure that this pressure remains within margins, turbo manufacturers have built in valves (wastegates). This valve ensures that exhaust gases no longer pass through the turbine housing but are directly discharged into the exhaust. This slows down the turbo.
The valve is controlled by a wastegate actuator, often called a pressure capsule in the Netherlands. From a certain turbo pressure, a rod pushes the valve further and further open until it is fully open, and a large portion of the exhaust gases go directly into the exhaust, thus "braking" the turbo.
Installation of a Boost Controller and Turbo Pressure Gauge – Increasing Turbo Pressure
Installing a boost controller on a Volvo 740/940 is relatively simple and will take approximately 30 minutes. As previously indicated, there is a limit to the turbo pressure with the original Volvo 740 and Volvo 940 ECU. To stay below this limit, a turbo pressure gauge will also need to be connected, so that the turbo pressure can be read precisely and the boost controller can be set correctly.
Below is an image showing how the boost controller should be connected.
Originally, a hose runs directly from the compressor housing on the turbo to the wastegate actuator or pressure capsule. This hose should be detached so that a T-piece can be inserted. This T-piece goes back to the pressure capsule and to the boost controller. The boost controller has an adjusting screw that regulates how much pressure will leak away, and thereby determines how much turbo pressure will be generated because the pressure capsule opens later, thus 'leaking' fewer exhaust gases.
Adjusting the boost controller
Every boost controller comes with a manual explaining how to adjust it. The operation is generally the same; screwing the knob all the way in means original turbo pressure, all the way out means maximum turbo pressure. To start, it is wise to screw the boost controller all the way in and then loosen it by 1 turn. Then drive for a bit to allow the engine to reach operating temperature. Once it's up to temperature, you can accelerate at full throttle while simultaneously checking 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 a small turn further each time and take a test drive until approximately 0.7 bar can be read on the turbo pressure gauge. With this turbo pressure, the Volvo B230 engine will feel significantly faster and deliver more power than when it left the factory.
More power and more turbo pressure!
The installation is complete, and you can now enjoy the cost-effective extra power that your Volvo 740/940 will now deliver.
Keep in mind that the more power is demanded from 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 and is not responsible for any damage caused by performing this modification.