Mitsubishi Lancer EVO VI-IX Intercooler Waterspray System

The Mitsubishi EVO is a fantastic car – originally conceived and designed with motor sport in mind, there are lots of smaller features built into the car in standard trim that are designed to assist Ralliart for competitive use in Group N rallying etc. The later model VII-IX’s are no exception, and one of the most often misunderstood features is the Intercooler Water Spray system.
However, like many things fitted to homoglated or road going versions of cars used in motor sport applications, the factory setup is very conservative. But this just leaves lots of room for improvement for owners looking to optimize the performance of their car – and we are more than happy to assist.
As part of our extensive R&D on the EVO range, we have spent a heap of time working out exactly how the system is setup and controlled – and how it is best modified to extract its optimum potential. Like a lot of late model cars, the automatic functionality of the EVO VII-IX intercooler water spray system is controlled via the engine management system. Fortunately we have access to all of the factory settings via EcuTek software, much the same as we have access to cam timing, ignition timing and fuel mapping.
But before we get into the finer details of the setup, you need to understand how and why it works – a lot of people know that pushing the button makes water spray over the intercooler, but what is the point of it?
When a turbo or supercharger compresses air, the temperature of this air increases dramatically. The hotter the air temperature, the less dense it becomes meaning the less power/torque your vehicle will produce. The more the air is compressed (ie the higher the boost pressure), the greater the temperature increases. Use of an intercooler means lower intake air temps, and more power/torque as a result (this is why your car always feels like it is at its best on a cool Winter evening!). Lower intake temperatures also reduce the risk of detonation or pre-ignition occurring.

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