PCV, GenV and Breather

Jfrost

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I blocked the PCV port on the GenV swapped L67 in my Fiero, something I've seen others do in this swap before. When the engine is shut off a hiss noise is heard which I traced to air escaping the oil dipstick tube, should have figured this would happen. Previously in my GTP I just routed a hose from the PCV outlet right to the throttle body, something I'd like to avoid on this for cosmetic reasons. Am I safe just running a breather filter on the PCV outlet?

I'd like some feedback as to what others have done and/or if I'm OK just running as is. When the engine's running, I don't notice air escaping the dipstick tube and it is not enough to move and/or push it out.
 

timboku

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Do you have an intercooler? You need to have a functioning pcv or you will blow out the crank seal, or spew oil out dip stick during wot runs...either a valve cover beather is needed or tube from pcv to tb after maf sensor.
 

Turbocharged400sbc

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be aware that some "ported" lim's have the slot next to the bbv opening on the gen 5 exposed (gen3 doesnt have this potential leak path) allowing manifold vacum/pressure to enter the crankcase.
 

Turbocharged400sbc

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did you block off the PCV valve nipple with a cap? or are you referring to the EVAP passage being plugged behind the TB? (g5 having a blower mounted evap solenoid that the gen3 has remote mounted, and runs to a nipple on the TB.

im guessing you have that verticle nipple on the blower plugged which m,eans, yeah, you have no fresh air supply.

the hiss is likely vacuum in the crankcase, aka you don't have a post maf, pre tb fresh air supply.

if its a N* tb adaptor I recall a guy machining the adaptor to route the N* fresh air passage to a nipple then to the nipple on the blower behind the evap solenoid boss.

either run a fresh air supply that is metered, or run an open breather and deal with any vac leak type issues via the tune (quite annoying since a metered fresh air supply is so simple and easy)
 

Jfrost

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did you block off the PCV valve nipple with a cap? or are you referring to the EVAP passage being plugged behind the TB? (g5 having a blower mounted evap solenoid that the gen3 has remote mounted, and runs to a nipple on the TB.

im guessing you have that verticle nipple on the blower plugged which m,eans, yeah, you have no fresh air supply.

the hiss is likely vacuum in the crankcase, aka you don't have a post maf, pre tb fresh air supply.

if its a N* tb adaptor I recall a guy machining the adaptor to route the N* fresh air passage to a nipple then to the nipple on the blower behind the evap solenoid boss.

either run a fresh air supply that is metered, or run an open breather and deal with any vac leak type issues via the tune (quite annoying since a metered fresh air supply is so simple and easy)
Thanks for the info. I've already run a hose from the PCV outlet in the GenV to the N* TB.

I do eventually plan to install an intercooler, most will have the PCV provision on them right?
 

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