Hey guys, I just saw a thread about blowby and it reminded me of something that I've been wondering about for a while. I know vacuum pumps are supposed to help seal rings better but if there is very high pressure above the ring and now because of the pump, there's negative pressure below the rings, then wouldn't the air have a stronger force pushing it past the rings? I'm not thinking of getting one but I'm one of those people that likes to know how things work and this is annoying me. Thanks for your input.
blowby For engine efficiency, a piston must have force pushing on the rod and crank with minimum resistance. Better yet, have pressure on top and vacuum on bottom and the piston will gain efficiency. Blowby builds up in the crankcase as pressure and contamination. At the same time oil gets above the rings and contaminates the combustion and the chamber. The oiled fuel mixture looses octaine and causes detonation. Carbon buildup adds more detonation....... an engine usually does not last long after blowby set in. Vacuum pumps can add horsepower to a real drag engine, but won't do much for a street/strip variety from what I hear.