She has a trace of blowby, 489" inch BB engine, a mild Crane Rumpity Rump cam and GM Performance aluminum oval port heads. I'm currently running a stock over the Chevy parts counter AC PCV for a 454. A strong running engine with a hint of oil vapor smell when driving. Is there a better alternative to use in the engine??
Factory engines breathers receive air thru the air cleaner to the PCV on the opposite side thru the rocker covers. Most performance engines leave them open for appearance. Before I installed a PCV system I ran a hose from the engine breath to the air filter and almost all the smell was gone. Both rocker covers need to have the factory style baffles Jim mentions. A 500 inch Cadillac or a 496 inch Chevrolet pickup engine may flow additional air.
https://mewagner.com/ I'm not even one of the cool kids, and I have two of them. Not both on the same car, of course . . .
Is this a fresh engine, etc? Do you have blowby with the oil fill cap removed, ie can you see the oil vapors? Only asking because if a fresh engine, rings may not be seated, if it’s been awhile running, may be other issues.
What he said. NOT the cheapest, but easily the best. You can dial them in to just about any combo. I struggled to find a PCV that would work well for my combo for a long time before just spending the dough. Glad I did.
Installed one on the Comet, works perfectly. The customer support is top notch, something that is rare these days.
It appears from their unit can be bought with an 1/2” hose adapter so it does not need to be used with a valve cover grommet. I do know a friend who installed one and liked it. He recently sold the vehicle.
I just installed a ME Wagner on my engine. There are videos on YouTube about these for larger big block engine installations. I watched 3 including the one from the company. With rocker cover style no additional parts are needed and it’s pretty easy. They are a very well made machined part. Might be expensive to some but to me it was not @ $130. They are made to tune for lower vacuum engines. The instructions are on line to read on their website and all that’s needed is a good vacuum test gauge. I bought a kit at Harbor Freight. I could not use the rocker cover grommet and bought their hose adapter. As a test: with your engine running remove the breather from the opposite side rocker cover from the PCV valve. There should be enough vacuum to hold a piece of paper on the grommet where the breather was. There are also explanations on how a PCV valve goes from idle mode to cruise mode letting in more engine vapor to the intake for combustion. Also the factory breather was not out in open air but plumbed to the air cleaner; if yours is open it’s why your smelling your engine.
Jim, you are correct. Factory 454’s with 450 hp had a pretty healthy cam and not the same vacuum as a pickup truck stocker. Since 2many says his 489” comes from a crank and not a big over bore he may have a fair amount of vacuum eventho his cam is not stock. Possibly the original 454/450 had a different PCV from the factory with different spring and orifice. I usually go overboard with explanations and finding a duel flow PCV intrigues me. ALL PCV valves change flow while driving because ANY acceleration drops vacuum and when the opposite side breather no longer is a path for vacuum into the engine it becomes pressure out and he smells it. If it were plumbed to the air cleaner as positive pressure vapor it would enter the carb and burn in the engine like an idling/cruising engine. Every aftermarket air cleaner I’ve seem has a punch out for a fitting for a closed system and there are push in breathers with a hose bib attached.
Had a similar occurrence on an Olds engine during break-in period. Mild cam, single 4 bbl. Had to ditch the flashy finned covers in favour of ones with better baffling. Reverted to breather on the Rh cover, PVC on the Left, problem solved
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