I would not recommend getting rid of the PVC.
Unless you have a big breather in the valve cover that won't blow oil everywhere.
Or you can run an electric vacuum pump to a catch can???
You might have too small of turbine housing like Tlowe said, also,your turbine wheel is too small.
Your engine is a 230, correct?
For now you can try and port the snot out of your turbine housing(really open up the exhaust port/entire turbine housing) if you do not want to spend money on a bigger turbine housing in order to get more exhaust flow.
20 inches @ idle is fine.
MBHD
