Not sure what "Pushrod" was disagreeing with, but here's the gist. The PCV, positive crankcase ventilation, was designed to do a couple things. 1st, to keep the crankcase vapors out of the environment to some degree and the oil slick down the center of the highway, and recirculate it back to the intake to be burned. A byproduct of that is that while the engine is running at idle and cruising speeds, 90% + of the time, it pulls a vacuum on the crankcase. So air comes in a breather and the engine vacuum pulls it out through the PCV. This vacuum helps keep from having positive pressure in the crankcase. A positive pressure "can", not "always", cause oil leaks. Supposedly each PCV valve is tailored to its specific engine. So theoretically they will not perform optimally on a modified engine. The Wagner is tunable. There have been magazine articles on this product, all with good reviews. There are many opinions, "if it's built right. If it's tuned right, it wont have any leaks and doesn't need a PCV valve, just 2 breathers". That is their opinion and I won't try to change that. For my engines, I like the idea and am hoping I have good results with it. As for the turbo jet boat, I'm also installing a vacuum pump for when the engine is under boost to help with the same issues, leaks and ring seal/blowby.