Look for the Kreen Internal Engine Cleaner. This stuff is supposedly better than a majority of the shit you get at autozone for cleaning your engine.
Ok, I just got off the phone with a tec person from the Kano Labs company, and he broke it down for me. This stuff is made to accually dissolve the carbon crud that is on your pistons, rings, and valves, while the other stuff you get from most auto stores are formulated to kinda lubricate the carbon in hopes of it breaking up. In other words, this stuff is supposed to be the shiat! They recommend you use it right before an oil change. $22.95 per gallon. What do you folks think?