What Do You Think Of This PCV Elimination Theory

[bison]

The added vacuum will pull the fuel right past the rings. It will mix with the oil and wont boil off. Ive seen it myself. Setup had 8 inches of vacuum.

Please keep in mind these engines were race engines that were built to run with a vacuum setup. Not one that was thrown on there to control oil leaks or blow by.

 

[BEATAV8]

eh? Why would oil get contaminated with fuel when running a vacuum in the crankcase? Any fuel that gets in there will boil off a lot easier at vacuum than it will at atmospheric pressure, so I don't get this.

John

I would theorize that the 5-8"Hg crankcase vacuum is stronger than the vacuum in the cylinder on the intake stroke, thus pulling fresh fuel/air past the rings during the intake stroke. (not likely to happen under boost, but is likely to happen at other times)

 

[bison]

I would theorize that the 5-8"Hg crankcase vacuum is stronger than the vacuum in the cylinder on the intake stroke, thus pulling fresh fuel/air past the rings during the intake stroke. (not likely to happen under boost, but is likely to happen at other times)

I made a few more phone calls. On an NA Windsor engine a friend ran 14-16 inches of vacuum and it made peak power in that range. He picked up nearly 30hp at the wheels in that vacuum range. Pulls a lot of fuel in the crankcase though.