I have been looking through the particle.dat files for this exact thing. Found an area that pertains to Black_Smoke and such, but have yet to understand the hex values attached to it. Only thing I have managed to do was freeze up my game after torpedo impact, so at least I know I'm on the right course.
There are quite a few variable that can be adjusted like how much comes out, wind coef, general velocity, weight, opacity....plent of stuff. Just not sure which bits to change, and as to what they represent. Here's screenshot of what I am seeing....
