Well, after cleaning all the years of baked on crap out of my intake, I've decided I might consider a PCV delete, but I have a few questions first.

From what I've read, this has no adverse affect on performance and the biggest issue is with the breather caps puking out oil, but this is a, "Your mileage may vary" situation.

So I guess basuically my only question is this. If I go ahead and remove the PCV system, is it as simple as just taking out the valve and hoses and replacing them with valve cover breathers? Is a chip re-program or ECM calibration necessary? Are there any other adverse effects I should expect on the car?

Thanks.

 

Shorter Oil Life
Crankcase moisture
Sludge buildup
Smell of oil on acceleration
Appearance of smoke under hood
oil film under hood giving the appearance of leaking
increased tendency to oil leaks.

Advantages:
None

 

I'd tend to think that sludge buildup on a valve cover which can wiped off is easier to deal with than sludge buildup inside the plenum and intake. That was an experience...

Shorter oil life I can deal with. I'm not the type of person who like sto drag every last mile out of an oil change anyways.

How do all of the other things you mentioned apply? I've been doing some reading and right now I'm leaning towards the fact that I'd rather not have all the sludge and hot crankcase gasses re-enter my intake.

 

the pcv helps to clear all that crap out of the inside of the motor.

I'm guessing the engine had long oil intervals, or low quality oil that built up near the egr ports, driven short distances, etc. these all contribute to sludge build up.

the pcv system in a normal naturally aspirated SBC is completely fine as it exists.

if you want to avoid all the sludge build up, use a synthetic or partial synthetic oil, and make sure the engine is run a good 30 minutes to an hour at least once a week. this helps get the internal up to temp and 'burn' off all the crap inside the engine, as well as the exhuast system.

you can't avoid buildup near the egr, as the high temp will coke the oil and create the sludge, unless you plug the egr ports on the heads.

 

Using better oil can reduce/eliminate buildup in the intake and plenum.

Water is a byproduct of combustion so any combustion gasses entering the crankcase carry water. Since the crankcase is relatively cool, the water condensates. PCV drops the pressure in the crankcase and encourages the flow of clean dry(er) air to purge the moist air. Once the engine heats up, PCV removes anything that condensed during warm up.
Water is an enemy of any motor oil as it will rapidly use up the additive package and accelerate the formation of sludge.
Those gasses have no measurable effect on idle/cruise operation and if the inlet breather is directed away from the intake there is no flow into the intake under acceleration.

 

Directed away from the intake?

 

PCV air enters through the air cleaner and then via a hose enters one valve cover. It then exits the other valve cover via the PCV valve and enters the intake air stream. When you accelerate, intake manifold pressure rises defeating the positive flow via the PCV valve. At this point, crankcase gasses flow back into the air stream via the previously defined inlet. If that inlet is given its own filter separate from the engine intake then those gasses will vent elsewhere. You may still face the stink on acceleration and oily mess where the gases vent but you will have no crankcase gasses entering the intake on acceleration.

 

Which I hear is a good thing. Think I might try the breather caps and see how it goes. If It's a big mess I'll put the PCV back on.

OK se Let's throw in a third option for a second here. Suppose I went with a breather can?

 

I agree with Texas there. I would not recommend removing your PCV. The symptoms you're describing are poor maintenance, not PCV problems.

Do a breather can - with your PCV system.

 

Look at the pictures I posted here and tell me what you think the problem is.


https://www.thirdgen.org/forums/tpi/...il-plenum.html

 

that's not too bad, actually. the plenum and runners on my brother's car was much worse. I had to scrub the throttle for quite awhile.

it's from bad valve seals, and EGR. this dumps oily carbon into the engine as well as exhaust.

I'm sure it was a combination of lazy pcv valve, bad valve seals, maybe quite a few years of build-up, and maybe not so great oil and long intervals.

I could take a picture of the 305 we took out of his car, but it's ugly.....

 

Pcv would be a small part of the intake build up. When you cut the engine off some of the intake valves are open letting the hot gases rise to the top and stop at the thottle valve. On a carb or TBI engine this is not a problem because the gas keeps the build up washed down.

 

looks pretty normal... think about how many years it took to accumulate that much crud eh?
Clean it up, and it won't be bad again in your lifetime... Keep the PCV tho, as long as your valve covers are baffled, you won't be seeing that stuff again for a while