Fixed Orifice PCV "Valve"
Thread Starter
Le Mans Master
Joined: Mar 2002
Posts: 5,955
Likes: 161
From: PNW
Thread Starter
Le Mans Master
Joined: Mar 2002
Posts: 5,955
Likes: 161
From: PNW
After talking to Roadrebel (Phil) he told me it was a MUST to run a seperate PCV valve on my system. Regardless of what year it is. I would NOT run a check valve. The cracking pressure is to high. Just run a regular old GM PCV valve. It completely eliminated my problem.
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
I'm building an LS2 stroker like Howie has and plan on doing some HPDE's once I get the car sorted out. I was hoping for some feedback on what I posted since I can't run the motor yet and confirm it. I had been fiddling with my PCV system for a while and had what seemed to be a pretty good setup for a h/c 346. However, this will be a built motor and will have looser clearances.
Melting Slicks
Joined: Apr 2007
Posts: 2,945
Likes: 1,115
From: Hereford AZ
.....a few thoughts.....
1) This is why I don't particularly like giant catch can reservoirs as a way to avoid emptying it for one year - potentially too much oil and water sitting there for too long.
2) If you are using an actual PCV valve, you need to allow it to be lubricated by the oil, hence, the location of the catch can between the PCV valve and the intake.
3) I'm convinced that almost any catch can will catch more if the air and oil are allowed to cool somewhat. This is one reason why I mount my filters away from the intense heat of the engine. The other reason is that most coalescing filters with metal reservoirs have a maximum operating temperature of 175-180F. You can buy larger versions with 250F temp limits, but they are very expensive.
1) This is why I don't particularly like giant catch can reservoirs as a way to avoid emptying it for one year - potentially too much oil and water sitting there for too long.
2) If you are using an actual PCV valve, you need to allow it to be lubricated by the oil, hence, the location of the catch can between the PCV valve and the intake.
3) I'm convinced that almost any catch can will catch more if the air and oil are allowed to cool somewhat. This is one reason why I mount my filters away from the intense heat of the engine. The other reason is that most coalescing filters with metal reservoirs have a maximum operating temperature of 175-180F. You can buy larger versions with 250F temp limits, but they are very expensive.
PS there is no requirement for the PCV valve (especially any fixed type) to be lubricated by (engine) oil.
I realize that the PCV decreases crank case pressure, but by definician it is considered a emission component; has little to do with WOT perfornmance.
Thread Starter
Le Mans Master
Joined: Mar 2002
Posts: 5,955
Likes: 161
From: PNW
I'm building an LS2 stroker like Howie has and plan on doing some HPDE's once I get the car sorted out. I was hoping for some feedback on what I posted since I can't run the motor yet and confirm it. I had been fiddling with my PCV system for a while and had what seemed to be a pretty good setup for a h/c 346. However, this will be a built motor and will have looser clearances.
http://forums.corvetteforum.com/show...7&postcount=48
Race Director
Joined: Dec 2000
Posts: 19,304
Likes: 85
From: San Diego CA
ok. I as I am sure alot of you are growing tired of this....Your points reveal you are thinking about it. First, if you have a catch can...consider emptying it periodically. (duh).... Secondly, the 'cooling' of the oil matters less, as the intent is to reduce oil consumption during hard acceleration/driving (the engine is hot). I can appreciate your pcv system...so now you have no problem...?
PS there is no requirement for the PCV valve (especially any fixed type) to be lubricated by (engine) oil.
I realize that the PCV decreases crank case pressure, but by definician it is considered a emission component; has little to do with WOT perfornmance.
