Turbo Actuator Kit for Mitsubishi Pajero 4D56 / Hyundai Galloper D4BH

Description

SAITO presents the dedicated kit consisting of an actuator, a replacement bolt for the safety valve, and an in-cabin boost gauge to increase turbo pressure on Pajero 4D56 / Galloper D4BH

By design, diesel engines benefit from a high air intake. In fact, if the air-to-fuel ratio shifts in favor of air (within certain limits), combustion efficiency improves, and combustion chamber temperatures decrease. Combustion in diesel engines is triggered by the increase in temperature due to the compression of air and fuel, enabled by the oxygen (oxidizer) contained in the air. Therefore, the greater the air supply, the better the combustion.

Older engines from the 1980s and 1990s, due to limited knowledge of turbocharging effects, modest material strength, and still-primitive aerodynamics, were turbocharged at low pressure—typically not exceeding 0.8 bar in the intake manifold. With technical progress, field experience, and improved turbochargers, it has been observed that increasing boost pressure provides benefits in terms of reduced fuel consumption and greater durability of components in the combustion chamber and exhaust system, including the turbocharger itself.

As engines age, the turbocharger tends to lose efficiency, reducing the air supply, while the fuel injection system, due to component wear, tends to deliver more fuel. This imbalance alters the air-to-fuel ratio in favor of fuel, increasing thermal load in the combustion chamber. The first symptoms usually appear as cylinder head cracks, typically in the hottest spot—between the two valves. This is often followed by exhaust manifold failure and internal cracking in the turbine housing. Clearly, increasing the air supply—within limits—is beneficial for engine component longevity and helps reduce specific fuel consumption.

On the 4D56 engine fitted to the Pajero and its derivatives (such as the Galloper’s D4BH), experience has shown that a pressure of around 1.2 bar in the intake manifold is beneficial—provided the engine is in good condition and there are no leaks around valve guides or between pistons and cylinders.

If you wish to increase boost pressure, it is important to remove the safety valve located on the intake manifold, and it is advisable to install a boost gauge to monitor operating pressures.

To increase boost pressure, SAITO offers a dedicated kit consisting of an actuator, a safety valve delete bolt, and an in-cabin boost gauge.

Applications: Mitsubishi Pajero, Hyundai Galloper
Displacement: 2.5L
Year: 1990 – 2000
Engine types: 4D56, D4BH

The kit includes:
1 x 1.1 BAR ACTUATOR
1 x SAFETY VALVE DELETE PLUG
1 x BOOST GAUGE