PCV valves instead of breathers?

Yellow73SB

Yellow73SB

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I don't have a pcv valve right now, Could I run two of them t'd together instead of breathers

Seems like it would help oil from pouring out of my breathers like it does now
 
NO, on account of what happens is the crankcase then goes to damn nearly intake mani vacuum, and that can't be good, somehow....

BUT, as a funny trick of the year, IF you have a leaking China wall on your intake and we know that is a PIA to fix just for a lousey little oil leak...you DO hook up two pcv valves and clean off the leaking area with carb cleaner best as possible outside....fire up the engine...and spray on the leak, you will hear it whistle and slurp up some cleaner a bit...kill the engine and let it dry off a bit....then redo the RTV sealer a bit, then restart the engine for about 2 seconds, kill it again....and dap some more on the outside.....

let it cure overnight.....

redo the plumbing correctly, and it's fixed....I did this for a leak back near the dizzy some time ago....it worked really well...and YES....

I"M LAZY.....

:bounce::bounce::devil::clobbered::zzz:
 
Better to just run downdraft tubes and furgetabout PCV valves. It's pollution crap and wasn't even used prior to 1963. Remove the guts of a PCV valve (or just make an elbow out of pipe) and attach a rubber hose down the side or back of the engine (keep it away from headers). Presto! No more gummy oil vapors going onto your spark plugs. Engine just burns gas and oxygen. Oh yeah...you will have oil stains on your driveway and in your garage. Just put a "drip pan" under it and don't worry about it. It's just your Vette marking it's territory :cool:
 
Thats exactly what i use DEP,i have a -12an line running from each vc down to where the charcoal can use to be,they are hooked up to a puke can thats vented out the bottom,keeps my vette from marking it's territory :amused:
 
I was actually just thinking, I'll make a breather box that two 10 an lines will run too, it will be higher than the engine so if oil does come out it will run back in

I'll mount in the windshield wiper tray
 
That weirdo GrandSportC3 had a setup where the PCV hose went into the header collector. The crankcase vapors were literally sucked out of the engine and into the exhaust where they were burned. They sell a setup like that somewhere. Either way...you still need a breather cap if you don't plan on using PCV.
 
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Tell you what strange though...with the L98 setup out of the valve covers with a PVC on one side and the other into the air induction before throttle blades....I had a fair amount of oiling...

then switching to the heavily modded LT1 mani on the same engine, I put the PCV on the intake as per stock, and one of the covers plugged and the other to the same airstream spot on the induction....

lots less oiling....go figger....no sense, just is....it is essentially pulling from the top center of the crank case, just like the old Pontiacs did in that lifter valley pan cover thing.... and I never had much oiling from the old Ponchos....

:D
 
DJ Dep said:
That weirdo GrandSportC3 had a setup where the PCV hose went into the header collector. The crankcase vapors were literally sucked out of the engine and into the exhaust where they were burned. They sell a setup like that somewhere. Either way...you still need a breather cap if you don't plan on using PCV.
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My uncle has that too on his 598 chevelle.
 
I used to have that too, and you don't need any fancy stuff. All you need is 2 of those AIR injection check valves and a short section of the tube they screw in (cut from headers). Cut the tube at a 45 degree angle and drill a hole in the top of the collector and position the tube with the valve so that the cut is perpendicular to the exhaust flow (vertical) and weld it in. Hook it to your valve covers and presto. If you hook it to both valve covers you need to drill the manifold for a breather.
 
That's it TT!! I think either Summit or Jegs sells it as a kit too. But it's not hard to fabricate. Supposed to work really good. Not sure if it would pass pollution testing though.
 
DJ Dep said:
Better to just run downdraft tubes and furgetabout PCV valves. It's pollution crap and wasn't even used prior to 1963. Remove the guts of a PCV valve (or just make an elbow out of pipe) and attach a rubber hose down the side or back of the engine (keep it away from headers). Presto! No more gummy oil vapors going onto your spark plugs. Engine just burns gas and oxygen. Oh yeah...you will have oil stains on your driveway and in your garage. Just put a "drip pan" under it and don't worry about it. It's just your Vette marking it's territory :cool:
Click to expand...


C'mon there Dep, if you just hang a 1lb coffee can under the end of that road draft tube it won't drip in the driveway. Or just park in the grass. Do you have to make EVERYTHING so difficult??:harhar:
 
TimAT said:
C'mon there Dep, if you just hang a 1lb coffee can under the end of that road draft tube it won't drip in the driveway. Or just park in the grass. Do you have to make EVERYTHING so difficult??:harhar:
Click to expand...

Hell Tim, if it was me I wouldn't give a dang if it dropped oil all over the place. I own a Harley. I'm used to it :)
 
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Yellow73SB said:
There is summit and mr gasket too



And at least when oil comes out it will be out the pipes
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LOL....I wondered about that. If you have blowby real bad you could look like a jet fighter going down the street. White or blue smoke trailing behind you :eek::D
 
Twin_Turbo said:
I used to have that too, and you don't need any fancy stuff. All you need is 2 of those AIR injection check valves and a short section of the tube they screw in (cut from headers). Cut the tube at a 45 degree angle and drill a hole in the top of the collector and position the tube with the valve so that the cut is perpendicular to the exhaust flow (vertical) and weld it in. Hook it to your valve covers and presto. If you hook it to both valve covers you need to drill the manifold for a breather.
Click to expand...

So doesn't the venturi tube restrict the exhaust?
 
big2bird said:
Twin_Turbo said:
I used to have that too, and you don't need any fancy stuff. All you need is 2 of those AIR injection check valves and a short section of the tube they screw in (cut from headers). Cut the tube at a 45 degree angle and drill a hole in the top of the collector and position the tube with the valve so that the cut is perpendicular to the exhaust flow (vertical) and weld it in. Hook it to your valve covers and presto. If you hook it to both valve covers you need to drill the manifold for a breather.
Click to expand...

So doesn't the venturi tube restrict the exhaust?
Click to expand...

Nope....when you weld it it sits flush with the inside of the header collector at a 45 degree angle. Nothing extends inside the collector at all. Did you ever notice those weird-looking vents cut in the sides of NASCAR stocker windows with the hoses attached? Same principle. The air, or in this case exhaust, passing by the openings creates a low pressure area that literally sucks the PCV vapors into the collector and out the pipes. For the NASCAR cars, they have the openings in the opposite direction so it blows cold air inside the drivers helmets.
 
I think when you weld the tube into the collector it's supposed to stick down 1/4"

Doing some searching it seems that it's worth at least 20 hp according to their claims

[ame]http://www.youtube.com/watch?v=wGrx2rvIxJ0[/ame]
 
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DJ Dep said:
TimAT said:
C'mon there Dep, if you just hang a 1lb coffee can under the end of that road draft tube it won't drip in the driveway. Or just park in the grass. Do you have to make EVERYTHING so difficult??:harhar:
Click to expand...

Hell Tim, if it was me I wouldn't give a dang if it dropped oil all over the place. I own a Harley. I'm used to it :)
Click to expand...



Harleys leak oil??????????? Damn.:amused:
 
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