a good reason to remove the stock pcv system is that it sucks up oil and can cause kr by reducing gas octane.

The only reason that manufacturers dont vent the crankcase to the atmosphere is because of EPA regulations and emmissions control

 

There's a little more to it than that...yes, PCV was originally designed to reduce emissions, but has since evolved. I don't believe that just a breather in the valve cover would be sufficient to remove condensation and moisture that could collect in the crankcase. Personally, I was never fond of cleaning the oil residue off of all my old sbc valve covers that would collect from my breathers either. If one was to remove the PCV, they should definitely have tuning software to compensate for it. I believe that it comes down to the application also...whether it's a daily driver or a full race vehicle, not to mention what area of the country you're in. Here in the northeast, I'd think that we're a bit more prone to condensation in the winter time than some of the warmer states.

As for the oil that is sucked into the intake and combustion chambers, I see your point, but I think that a good oil catch can system will decrease that greatly. That, combined with periodic top-end/induction services (such as SeaFoam, GM Top End Cleaner, BG Induction Service, etc.), will help to keep the induction system as carbon-free as is possible.

 

Condensation and moisture collects in the engine regardless of whether there is a breather on the pcv or not this is why your engine is designed to run at 210 to boil the water off and also why water comes out the tail pipe when you crank it in the morning regardless of pcv configuration rapid cooling and differences between temperature will cause condensation whehter it be on your windshield or inside the engine a compartment can be completely sealed and the moisture in the sealed compartment can still condense with variance in temp. Condensation isnt a factor. Epa regulation is.

Not trying to be argumentative, I just dont see condensation being a factor.

 

Any air introduced after the MAF sensor will be unmetered (why one shouldn't use a valve cover breather unless using a vaccum pump or exhaust venturi to replace the PCV system). Since the system is designed to recirculate the air, unless there is a restriction in the R/H vent tube connecting the R/H valve cover to the T.B. (I didn't check yet), then the system cannot draw a vaccum on the crankcase. It will simply burn off the gasses created in the crankcase and prevent a positive pressure from occuring.

 

I run in Speed Density so maf doesnt matter, but in any case any air that has entered the engine is accounted for because the crank case is positive and the intake line is plugged.

 

No worries...not an argument, just a technical discussion. I would consider condensation a factor though, since water has a lower boiling point in a vacuum, which can't be obtained with with just a breather.

Just my opinion, but I'm more prone to trust modern technology than old methods in this case. Today's engines and engine control systems are night and day in comparison to the old school ones that ran on leaded fuel, with soft valve seats, solid lifters, points, carburetors, and no emissions equipment. Also, today's engines are expected to last longer than the 1 year 12,000 mile warranties that the breather equipped vehicles came with. Just because a vehicle system was designed to please the EPA, doesn't mean that it doesn't have redeeming qualities also...take EGR valves for instance. Their original design and intent was to decrease exhaust emissions...in the process they lowered cylinder temps and NOx emissions, which can allow us to run more timing and gain more performance. Taken one step further, the technology has developed to the point that these emissions can now be obtained without the use of EGR valves.

I'm looking at it from the standpoint of a daily driven fuel injected street truck though, without the use of tuning software.

 

Im planning on putting a billet crankcase vent/filter on and plugging the intake line. Ill post up on it.

Here's an experiment put tape over the pcv to plug it leave it dangling with the crankcase left open, the engine idles and drives fine, if anything it will drive better because you wont have any oil consumption decreasing octane.

The only reason to have a positive crankcase vented into the intake is for emmissions.

 

I assume you are talking about some sort of charging system. I'm gonna leave it at that, I'm tired of explaining this. Yall can figure this out on your own through trial and error.