Quote: My guess would be at full throttle the pcv valve is closing And the crankcase is pressurizing. The other breather can't keep up. When the crankcase pressurizes it pushes oil up into the cylinders. Your best bet would be to install a vacuum pump. Gzmotorsports, Jonesracing, and Product Engineering all have Street vacuum pumps for continuous duty.
A good PCV valve should not close under WOT/heavy load. When man vac. is high(idle,cruise,light load) the PCV valve restricts flow to maintain a balanced air-fuel mix.It also prevents drawing oil out of the crankcase because of high manifold vac. At WOT,low vac,heavy load the valve OPENS to allow airflow through the crankcase. This is right out of a textbook. A PCV valve is more than just a check valve.
