Where to place nozzles?
I'm going to be boosting in the 20 to 25 psi range on a 2l engine and on the outside could make 350 to 400hp. The car is being set-up specifically to autocross and road race and I can make any changes that I want.
Due to the nature of autocrossing, I need a quick spool turbo which also will spool high. Which means that I need to make concessions about where on the efficiency islands of the turbo I can run. Basically, I'm going to be running in the 65% efficiency range at the high end. That means heat.
I have heard that you should not place the water injector(s) before the IC, why is that? My thoughts were that it would take some of the heat out of the charge before it hits the IC. Although it would remove some of the efficiency out of the IC, it wouldn't heat soak as fast. Plus, I'm going to be running multiple injectors so one before and one after the IC would be in the works.
In addition, wouldn't injecting water between the turbo and IC increase the efficiency of the turbo? Assume the first restriction after the turbo is the IC. If we cool the air charge between the turbo and IC, we would reduce the volume of air by reducing the temperature. That volume decrease would also result in a defacto pressure drop. With a pressure drop, the turbo could pump more air into that area easier. Resulting in a more dense charge with the same pressure. Or am I thinking about that wrong? Or is the resulting "steam" from the injector going to increase the volume and pressure?
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