PCV power limits

[NismoJ30]

Alot of the Z builds I look at keep the stock PCV set up and do not ditch it for a catch can set up. What is the most the stock PCV system can handle before a upgrade is necessary?

[evildky]

infinite, the pcv system is not efected by the amount of power your engine makes, it;s simply allows the air the passes by the engien rings to circulate back into the intake track, the only benefit of upgrading to a catch car is if the engine rings are wearign and you are getting excessive blowby you cna keep form burning oil

[NismoJ30]

Cool. So all the people that upgrade their pcv system in other cars (KA and SR ppl) are doing it for no reason?

[evildky]

most of these guys do it because they think a catch can looks cool, here's the thing, PCV = Positive Crankcase Ventalation, this means it's letting pressurized gases out fo the cran case, these gasses are formed from heat and ring blowby, the Z32 as well as just about every other nissan uses a metered air engine managment, so they pipe these gasses back into the intake tract between the mas and the engine (the PCV valve actually keeps more air from going into the crank case), if you are ever putting more air into your crankcase then your pcv valves can let out you have bad rings and need to rebuild your engine

people do lots fo stupid things because they think it's cool, like atmospheric bov's, these cause a rich condition every time theyblow off, thats why the z32 came with recirculating type bov's, anyone that adds atmospheric bov to a metered air car is decreasing performance and does so because they are 16 and think the woosh noise is cool

[NismoJ30]

Sorry if it seems like im over analyzing but I just want full understanding and I wanna pick ur brain

So if you have metered air management the stock PCV will be more that enough. But what if you have something that uses a MAP sensor?

[evildky]

no, stock pcv is good enough for anything, catch cans are better for a map based system but still nto needed unless there is serious engine wear or an extreme race only engine like you find on pro level drag cars

atmospheric bov's are fine for use wiht a map based system but on a metered air system actually are hurt performance

bottom line, there is no reason for you to do anytign wiht yur pcv system aside fomr new replacement pcv valves to replace old leaking ones