On this 302, would it be better for mw to go stock pcv setup or just run 2 valve cover breathers? And why? Thanks
The PCV system is the earliest smog device devised and one of the best things that was ever invented, pulls condensation and acidic vapors out of engine to be reburned. I'm using a 1967 setup that uses a open (vented to atmosphere) breather cap, oil fill can be seen on my blue engine picture. Beginning in '68 the cap was required to be vented into air cleaner, thus removing possibility of vapors reaching atmosphere. In the '70s Ford switched to a backasswards system, with PCV valve in breather cap and valve cover vented into air cleaner.
Having worked on many pre-pcv engines, I can tell you it is night and day difference on how much sludge gets built up inside the engines. The old engines often had a tube sticking down that relied on air passing by it to draft out crankcase vapors while traveling down the road. PCV is one thing you do not want to eliminate.
Yep. PCV is always advised for street cars due to above mentioned reasons. Next best is remote filtered catch can with dual header evac setup but you need a really decent flowing exhaust system to see full benefit. From there we get into vac pump setups but for once.. I digress. Lol
In my opinion unless running boost or engine has really poor ring seal, a catch can is just for looks.
I'd go along with that for 90% of typical street cars running around. The thing I do like about filtered catch cans is that they help keep the valve covers cleaner. Can't say all cars have perfect ring seal, especially over the life of the engine and not much else disappoints like seeing a beatifuly detailed motor with oil draining off those cool looking valve cover filters. The other thing many don't know about pcv setups is that they actually help ring seal. Same goes for restrictive air filters and exhausts too. Not that we really want those things on our hotrods but just an interesting sidenote of what helps push or suck the rings against the bores is all.