Today we are talking about the Toyota Celica GT4 ST185 or ST205 and installing the Wolf V500 Plugin Engine Management System.

Just a few of the benefits of installing the Plugin Kit onto the GT4 are that we have full control over Boost, Fuel, Ignition, and a huge range of other systems and parameters.

On of the things with the GT4’s, is that if you start increasing the boost and the amount of power produced, you will start to run out of fuel delivery. You will need to increase the injector sizing. Many larger injectors are low impedance, which in the case of the V500, is not a problem, as the V500 can control injectors down to 0.8 Ohms.

Another great advantage when removing the original ECU, and replacing it with performance aftermarket ECU, is that you can completely remove the original flap style Air Flow Meter, and put a tube in its place. This allows more flow to the turbo, and can help with increased boost levels and turbo / engine efficiency.

The original ECU in the GT4 is on top of the transmission tunnel, under the radio. When removing the original ECU out of the Toyota Celica GT4, there are bolts on both sides of the ECU that must be removed. The ECU can then be removed by pulling it out into the passenger footwell.

You then unclip the 3 connectors by pressing down the clips on top of each of the connectors. Now the loom is easy to access and ready for you to plug in the V500.

To fit up the V500 Plugin Kit, is as simple as pluging in the 3 plugs in the original loom into the 3 bays that match these plugs in the Wolf Plugin Harness. There are 3 different sized plugs so it is not possible to connect these plugs incorrectly.

Now, we plug the V500 into the other end of the Plugin Harness.

We have run a vacuum line from the engine intake manifold to the ECU. This vacuum source must be showing full vacuum / boost. Do not use a vacuum port where the vacuum or boost can be different from the boost or vacuum in the manifold. This can occur where boost is bled off for wastegate control, or a transition port in the throttle body. Both of these ports may show different boost or vacuum compared to the actual manifold boost or vacuum.

Plug this vacuum line into the V500.

Once you have the V500 connected to the GT4, it’s time to check that we have power, and that the car starts with the base tune that is supplied with the ECU.

When you turn on the key, you will see a green light on the end of the V500, showing that ECU is powered up.

When you crank the engine, the light will turn yellow, and once the ECU has enough information to synchronize to the engine, the light will turn blue and the engine will start.

So, once you have installed the V500, it starts and runs, the next step is to check the ignition timing and get it ready for the dyno.

When we say, “Get it ready for the dyno”, what we mean by that is that you must check hose clamps, check for water leaks, make sure all of your intercooler piping is tight. There is nothing worse than getting onto a dyno and having problems.