Does anyone see any marked benefit in adding a water spray to our aftercooler? I noticed some new STis have an option of adding a water pump to spray their intercooler.

 

We have an air to water intercooler, compared to an STi which has an air to air intercooler. The air to air intercooler benefits from water spray or nitrous spray much more so than our air to water.

One of the main reasons why this is the case is that in an air to air setup the actual boost charge is running through the intercooler; this means that the water on the intercooler directly affects the charge. On our setup you would just be cooling the water which will cool the boost once it reaches the intake manifold. So say you were able to cool your water down by 10 degrees, you wouldn't drop that much heat in the actual intake charge, but on an air to air, when heat is dropped it is heat directly from the boost.