Hi!
I have been reading the posts above and I see some really nice looking systems that you are using for crankcase evacuation.
The positive crankase ventilation system was mandated by federal law in september 1966. Its sole purpose is to capture the very toxic mixture of residual air-fuel mixture that gets blown by the piston rings and into the crankcase, plus airborne lube particles that form insde the crankcase. It is a very violent place to be on any given day!
The PCV valve must be located, either in the center of the intake manifold or on either valve cover. It must be completely airtight, mounted in a gromet or pressed into a sealed container like in the pictures of the Summit setup above. This is where air gets sucked out, but only as far as compression pulses will open the check ball inside the valve casing, assisted by the engine vacuum signal.
If you suck out air, you need to have a place for it to get sucked in too. That place is the breather on the other side of the engine, or as on older FEs, through the filler / breather cap on the filler tube on the intake manifold. This, however is not an ideal setup. If you want maximum cleanup effect, you really need to have the exit and entrance on the valve covers. This is due to the fact that
oil mist, gasoline fumes and water vapors tend to rise to the roof of the building, i.e. the valve covers. Since the FE with its Cobra LeMans or Baldie valve covers is one very tall building, this is where your culprit is going to reside and cause a mess, causing
oil stains and what not all over.
So, in my view and from what I have read, the valve covers need to be the north and south borders in this war.
The PCV valves are made in a myriad of configurations. What varies is mostly diamter and weight of the check ball. This is regulated by the vacuum signal that each particular engine is known to have. That means STOCK engines that idle smoothly AND have a regualr vacuum signal at 650-700RPMS.
As you get into more aggressive cam profiles, the vacuum signal starts to change and deteriorate in more ways than we can count. As we get into degree territories above 235-240° @.o50 on the FE, you need to look at other options. Notably vacuum pumps (with aggressive cams and low pressure piston rings) and / or
oil accumulators and scavenging systems that operate on header collector negative pressur. But on those applications you are always having to endure very discomforting and potentially deadly vapors inside your cars as you sit at the local stoplight.
The PCV system is the single most effective, least expensive and most reliable method of pollution control ever installed on an internal combustion engine.
bye
PCV blues
Hybrid Mode
