HP500 PCV Valve
 

Anyone ever replace one with a pcv from pep boys or napa or something? I am just wondering if the merc one is anything special since it goes right into the lifter valley.

Ive found there isnt much 'special' parts when it comes to merc stuff, except the price. Like the 600/800SC supercharger belt tensioners i have. list price is 640.00 from merc. Funny, there is a GM # stamped into the tensioner. Looked it up online, about 60 bucks from the chevy dealer. Same tensioner used in the LT1 vette engines. But, it doesnt come painted blue. So if the blue paint is worth an extra 580 bucks to you, then you gotta go merc.

I think you should be safe to take your PCV valve down to pep boys, and match it up.

I don't have one to actually match it up. I wonder how much difference there is between pcv valves.

I have one, I'll see if there is a part # on it

it looks just like one u would find in a small block valve cover

Any chance of a picture of it?

I'm in the same boat, have the valve covers but no PCV valves. If anyone knows the generic automotive part number that would be helpful. have a supercharged 502 that were just straight pass thru, no check valve. Seemed to work good but no part # for those either.

I would recommend you look up in the older GM Performance catalogue for the GM 502 Ram Jet efi engine and use that part number spec. PCV vlave assembly for that engine as it was fuel injected 502 engine with just about the same identical PCV crankcase volume and manifold pressure requirements. It will be a lot cheaper from GM or aftermarket for that engine.

Best Regards,
Ray @ Raylar

Sooooo.........I bit the bullet and ordered 2 of these from Mercury Marine. They are Mercury part #848578. The damn things cost me $15 each and $8 to ship from Mercury to me. So $38 total.....

They are still in the sealed quicksilver bags, funny thing is the PCV valves actually say ACDELCO CV856C on them.

So to everyone else, just go to pepboys or even look on amazon.com....they are $7 each there

Does AC Delco also make the rubber grommet the valve sits in? Merc # 811553.

fixx
 

go to your locak ap place ,,help products make them..

Where do they feed into the induction system? On most automotive carburetors, there is a large vacuum port on the carburetor base where you run the PCV hose. Can't recall if my Holley carb has that fitting on it.

pcv valves use spring tension and hole(orifice) size on bottom. when i was younger used to swap pcv valves and it would effect engine, either pull or hold oil in valve cover, foaming. orifice and spring effects to idle characteristics and function. early carbs did not have pcv or any ports, mid 90's carbs seemed when pcv made it to engines.

On the hp500 intake they pull from the intake base and are plumbed into the intake plenum just under the carburetor.