Freshdot

i was just told that my PCV and the box behind the manifold should be removed and then vent my valve cover, otherwise boost will cause crankcase pressure to rise and surge through my intake manifold? can anyone verify whats going on here? i have a mild build, greddy 18G, 10PSI, 310CC injectors, and will be doing S300 and getting tuned soon.

thanx in advance.

cleansi

there are a lot of threads on h-t about catch cans and ventilation of crank case pressure, please do a search

basically you have positive pressure in the internals of your motor if not properly ventilated oil and gases will force there way out causing harm to your motor and wallet.

Freshdot

thank you, no one explained to me how important this is when installing my turbo..also why wouldn't a company like greddy have mentioned this in their instruction manual if its that important? i thought these turbo kits were plug and play units designed to work on a factory car with little or no modification?

Westrock2000

I would guess the answer is becuase PCV's that recirulate into the intake tract are required by federal emmisions. Catch cans as far as I know are illegal on street cars. Even turbocharged and supercharged cars from the factory draw oil vapor through the intake and get oil all over stuff.