shook0002

The vacuum u feel is from the pcv valve sucking in crankcase gasses. Just revving won't build boost, it has to be under load to really spool the turbos up enough. Powerbraking willl build some boost, but I'm sure it won't build up enough to actually feel coming out, theres just not enough blowby on a new motor.

shingi

So the turbo inlet will actually be sucking out air from the driver side valve cover when in boost condition correct?, If I understand you correctly, then what you are saying is that I can't feel any suction on the turbo inlet because I'm simply revving it and there's no load. So if she is put on the dyno and actually spinning the wheels, the turbo inlet would be sucking air from the valve cover then, which at this point then the PVC is close correct.

bubbabud

The turbo inlet is only sucking air through the air filter if the filter is clean and the intake is not restricted it will not suck through the vent hose. the movment of air is controled by the blowby presure in the crankcase under light load or idle the pcv valve is pulling the blowby out of the crankcase and into the intake manifold to be burned. This in turn draws clean filterd air from the turbo inlet tract to replace the air the pcv valve has sucked out. when the load inceases the vacume drops and the blowby increases so the pcv valve can no longer handle it this puts a positive pressure in the crankcase this pressure is vented into the pre turbo intake stream where it is compressed and fed to the engine. so the air moves both ways through the vent depending on engine load and the amount of blowby sorry for the long rant but I cant explain it any better.

shingi

bubbabud,

thanks for the clarification. that was the answer i was looking for.
thanks everyone for contributing.

tjs50fx2

that is a crankcase breather line.
it IS NOT metered air from your air intake system.
you could simply run a vented catch can from the valve cover to catch any oil blowby and still allow the crankcase to breathe properly. you would just cap off the hose fitting on the intake tube to seal that up. the reason for running a catch can is to prevent any oily residue from the crankcase getting into your air intake system. This is a very common mod with boosted vehicles. i run one on my turbo mustang and it works great. I hope this explained it good enough for you.

05mustang_tt_charged

There isn't a MAF on the truck. It is run of MAP. The driver side vent will not see much crank case pressure as the motor pushes air to the passenger side naturally due to the engine spinning in a clockwise direction. It is naturally pulling air down on the drivers side.

I have a Mustang and when I had a Kenne Bell on it the passenger side would vent through the filters I had on the PCV barb but not on the drivers side. I noticed every time on the dyno it would expel fumes from the passenger side and I did have oil residue on the cam cover.