So after taking my intercooler off and the plastic tube that goes from the throttle housing to the super charger I was amazed how oily it was. The throttle body took forever to clean as did the rest of the components. I know lots of people think a catch can is not needed but I am no longer convinced. Has any here used a catch can long term and been able to see if it does help keep everything clean? As a side note I replaced my bypass valve.the one that was on the car was very easy to open. The DT one is nice and tight. This should help on early boost.