Forced Induction Superchargers | Turbochargers | Intercoolers

Too much boost in the crank case???

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Old Sep 2, 2005 | 12:59 AM
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Default Too much boost in the crank case???

Hey guys, I have a 370cid. and an sts GT 67 kit. We were tunning and when I hit 8psi. or higher the oil return line for the turbo (which goes into the oil filler cap) starts to pop out of the valve cover. There's too much pressure in the motor so it's stopping the oil from coming in through the oil filler cap. So we put a "puke tank" which is basically a hose coming off the valve cover to relieve pressure into a breathable catch can. But the pressure is still building up and pushing the oil filler neck out of the valve cover. Any body have any ideas??? Thanks
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Old Sep 2, 2005 | 01:35 AM
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You need extra and/or bigger breathers when you supercharge a motor.

I had to go to 2 small breathers on each valve cover, and a crankcase breather straight out of the front right of the oil pan. Even now when I really rev it to 6200, I get a little oil puking out of the K&Ns, so I'm not completely sure I have enough breathing yet.

Good luck,

Jim
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Old Sep 2, 2005 | 02:09 AM
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The sts kit comes with a check valve arrangement to keep the pcv line blocked under boost. Make sure it is wired properly. If not, you get full boost pressure directly into the crankcase.
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Old Sep 2, 2005 | 02:29 AM
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I can't use valve breathers because the oil return line from the turbo goes back into the oil cap, and the little block next to my oil filter we tapped into for the oil line to the turbo.

The little vacum re-arranger that bolts to the thermostat? It didn't seem to be working so we took it off. That really works?
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Old Sep 3, 2005 | 02:55 PM
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Originally Posted by jv_Z28
I can't use valve breathers because the oil return line from the turbo goes back into the oil cap, and the little block next to my oil filter we tapped into for the oil line to the turbo.

The little vacum re-arranger that bolts to the thermostat? It didn't seem to be working so we took it off. That really works?
Uhhh...if you took out that solenoid, every time you're under boost, you are blowing all of that pressure down into the crankcase!
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Old Sep 5, 2005 | 01:12 AM
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Install A Pcv Valve On Your Vaccum Line, We Installed A Sts Turbo And It Came With A Crank Case Solenoid To Be Installed On The Passenger Side Front Valve Cover But The 05 Trucks Have Anothr Vaccum Hose With Out Pcv Going To The Rear Of The Driver's Side Valve Cover And It Would Leak Boost In To The Crank Case So We Just Put A Pcv Valve On That Hose And Took Care Of The Problem.
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Old Sep 5, 2005 | 01:17 AM
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breathers


Originally Posted by jv_Z28
Hey guys, I have a 370cid. and an sts GT 67 kit. We were tunning and when I hit 8psi. or higher the oil return line for the turbo (which goes into the oil filler cap) starts to pop out of the valve cover. There's too much pressure in the motor so it's stopping the oil from coming in through the oil filler cap. So we put a "puke tank" which is basically a hose coming off the valve cover to relieve pressure into a breathable catch can. But the pressure is still building up and pushing the oil filler neck out of the valve cover. Any body have any ideas??? Thanks
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Old Sep 5, 2005 | 03:32 AM
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buy a passenger side valve cover and install it backwards on the drivers side head. You can put a breather on the drivers side like this, while still keeping your STS return. Work out your PCV problems ASAP
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