Crankcase pressure issue when in boost???

[Velocity10gear]

So I have a vortech v7 kit on my '20 gt pp1. its running a 3.25 pulley and the current engine mods are MMR Billet Oil Pump Gears and crank sprocket as well as NGK 6510 spark plugs. I had an issue before when I installed breather filters on my driver and passenger side pcv valves, the driver side breather wasnt seated properly into the valve due to fitment issues due because of a tank being beside it- so i solved that by installing a upr dual inlet catchcan breather. no more leaks are coming from the valve. Now im just trying to pinpoint the cause of the leak, because after driving it today when under boost with the 3.25 pulley, i noticed smoke from underneath my hood coming from the driver side. It seems as if some liquid or oil seeped onto the headers and caused that. Has anyone encountered something like this? Any idea what could be causing it?

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[Basspro302]

Check the valve cover bolts they loosen up, my car did the same thing.

 

[SheepDog]

So I have a vortech v7 kit on my '20 gt pp1. its running a 3.25 pulley and the current engine mods are MMR Billet Oil Pump Gears and crank sprocket as well as NGK 6510 spark plugs. I had an issue before when I installed breather filters on my driver and passenger side pcv valves, the driver side breather wasnt seated properly into the valve due to fitment issues due because of a tank being beside it- so i solved that by installing a upr dual inlet catchcan breather. no more leaks are coming from the valve. Now im just trying to pinpoint the cause of the leak, because after driving it today when under boost with the 3.25 pulley, i noticed smoke from underneath my hood coming from the driver side. It seems as if some liquid or oil seeped onto the headers and caused that. Has anyone encountered something like this? Any idea what could be causing it?

If you are running a dual breather setup, get ride of the PCV valve, it is only a restriction.

 

[horsepower addiction]

smoke test it

 

[Velocity10gear]

So guys I took it to my builder, and the problem was that oil was creeping out of the valve cover seal due to it not being fully seated. The loose screws were tightened and everything has been fine since

 

[Velocity10gear]

If you are running a dual breather setup, get ride of the PCV valve, it is only a restriction.

could you elaborate please? I'd like to understand

 

[Velocity10gear]

Check the valve cover bolts they loosen up, my car did the same thing.

it's so crazy that you said that, because that's EXACTLY what the problem was. Is this something that's happened multiple times to you, or was this a one time occurrence?

 

[SheepDog]

could you elaborate please? I'd like to understand

Sure. If you have both valve covers plumbed to a vented catch can, and the PCV system is not being used in the way OEM intended ( I assume you are boosted, and that the port on the intake manifold is no longer attached to the passenger side valve cover/PCV) then you want is little restriction as possible on both valve cover breathers.

The OEM design is as such - the driver side valve cover breather plumbs to the intake tube, after the air filter as serves as the inlet, meaning that when the the throttle is closed or nearly closed, there is vacuum present in the intake manifold. This vacuum pulls on the passenger side valve cover, and draws fresh air in via the drivers side. This is designed to recirculate the oil and fuel vapors that end up in the crankcase, back into the engine so that they are not being dumped into the atmosphere. (All EPA/emissions related). One of the issues with forced induction, is that you now have positive pressure on both valve cover breathers when in boost, so the drivers side tube is plumbing that blowby right back into your supercharger, and into you intercooler and back to the engine

When you go forced induction, you are now pressurizing the crankcase due to the blowby pressure from the turbo/supercharger that forces its way past the piston rings. Because the OEM PCV system only functions when the throttle is shut, it does not help to alleviate this additional pressure when in boost/throttle open. Now, the only way the pressure can escape the crankcase when you are on the throttle, is through the ports on the valve covers. If you still have the PCV valve on the passenger side, it is creating a restriction for that pressure to escape because the gap between the ball and seat of the valve is very small.

In Summary- if you are FI, you want valve cover ports with no PCV or check valve in place, and you want as large of lines to the catch can as possible (like 10 or even 12 AN) This will keep the intake completely clean and free of blowby shmeg, an prevent any pressure from building in the crankcase that can potentially blow out main seals, valve cover gaskets, oil pan gasket etc.

 

[illtal]

Not true for pd superchargers, it functions like stock because the intake is constantly under vacuum. Only time there is boost is inside of the top mounted unit.

 

[Basspro302]

it's so crazy that you said that, because that's EXACTLY what the problem was. Is this something that's happened multiple times to you, or was this a one time occurrence?

Gen 1 coyotes had more bolts along the rail, gen 2 they removed some bolts but still had the threads in the cylinder head so they released a tsb to drill the valve covers and install bolts. Gen 3 they removed both even tho they knew about the issue. So get a swivel socket and check them often on the gen 3. Blue loctite on the bolts will probably help them from backing off. Do not use red loctite!

 

[SheepDog]

Not true for pd superchargers, it functions like stock because the intake is constantly under vacuum. Only time there is boost is inside of the top mounted unit.

OP has a Vortec

 

[horsepower addiction]

Not true for pd superchargers, it functions like stock because the intake is constantly under vacuum. Only time there is boost is inside of the top mounted unit.

not exactly. the problem is that you are now pressurizing the crankcase. so both valve covers/pcv system is pressurized. it is not designed to work like this. so you still need to remove the pcv or you will over pressurize the crankcase and start loosing a lot of power
with boost its best to let it breath free or vacuum it out when under boost

 

[horsepower addiction]

Gen 1 coyotes had more bolts along the rail, gen 2 they removed some bolts but still had the threads in the cylinder head so they released a tsb to drill the valve covers and install bolts. Gen 3 they removed both even tho they knew about the issue. So get a swivel socket and check them often on the gen 3. Blue loctite on the bolts will probably help them from backing off. Do not use red loctite!

just drill the rest of the wholes and add the rest of the bolts

 

[illtal]

not exactly. the problem is that you are now pressurizing the crankcase. so both valve covers/pcv system is pressurized. it is not designed to work like this. so you still need to remove the pcv or you will over pressurize the crankcase and start loosing a lot of power
with boost its best to let it breath free or vacuum it out when under boost

The intake on a PD is under vacuum, the crankcase regardless of boost that has bled down from the cylinders, it does have a constant vacuum on the PCV situation. Without putting a pressure gauge on it I would assume since the amount of air sucked out would be much greater than an N/A car.

The limitation to how much vacuum produced the intake is directly influenced by the size of the TB and intake tract on a PD supercharger.

The real question is how efficient is the stock PCV system at expelling built up crankcase pressure for the other types of boost that places boost in the charge piping going to the intake. In that situation there will be boost built up, unless it's on a breather setup or cans vented to atmosphere. I guess one could plum it back to the intake to ensure all boost is expelled from the system under vacuum.

 

[Bonedizzle]

I am not having any issues currently, but here is my setup with my ESS kit.
I have a breather on the drivers side valve cover.
I have the UPR one way breather on the oil fill cap.
I have a JLT 3.0 catch can on the passenger valve cover to intake, with the PCV intact.

Should I gut the PCV for the catch can? I did have it gutted when i ran just breathers, but put the check valve back in for the catch can.

Sure. If you have both valve covers plumbed to a vented catch can, and the PCV system is not being used in the way OEM intended ( I assume you are boosted, and that the port on the intake manifold is no longer attached to the passenger side valve cover/PCV) then you want is little restriction as possible on both valve cover breathers.

The OEM design is as such - the driver side valve cover breather plumbs to the intake tube, after the air filter as serves as the inlet, meaning that when the the throttle is closed or nearly closed, there is vacuum present in the intake manifold. This vacuum pulls on the passenger side valve cover, and draws fresh air in via the drivers side. This is designed to recirculate the oil and fuel vapors that end up in the crankcase, back into the engine so that they are not being dumped into the atmosphere. (All EPA/emissions related). One of the issues with forced induction, is that you now have positive pressure on both valve cover breathers when in boost, so the drivers side tube is plumbing that blowby right back into your supercharger, and into you intercooler and back to the engine

When you go forced induction, you are now pressurizing the crankcase due to the blowby pressure from the turbo/supercharger that forces its way past the piston rings. Because the OEM PCV system only functions when the throttle is shut, it does not help to alleviate this additional pressure when in boost/throttle open. Now, the only way the pressure can escape the crankcase when you are on the throttle, is through the ports on the valve covers. If you still have the PCV valve on the passenger side, it is creating a restriction for that pressure to escape because the gap between the ball and seat of the valve is very small.

In Summary- if you are FI, you want valve cover ports with no PCV or check valve in place, and you want as large of lines to the catch can as possible (like 10 or even 12 AN) This will keep the intake completely clean and free of blowby shmeg, an prevent any pressure from building in the crankcase that can potentially blow out main seals, valve cover gaskets, oil pan gasket etc.

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