Crankcase Ventilation
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From: North Carolina
Actually nothing Gene. On a stock n/a or boosted vehicles nothing is changed. The throttle body gets dirty and if you have throttle secondaries (like our trucks have stock, my 99 SHO had them) they get gummed up with the oil and carbon and eventually throw a code for the IRCM Intake Runner Control Module not working. Code P1518 or P1538. The little motor can't open or close the throttle secondaries due to the oil and carbon deposits.
On a stock boosted motor you don't have the throttle secondaries so you end up with the oil and carbon deposits on the rotors of the blower and coating the intercooler. So at some point you need to remove the blower and clean the intercooler.
On a stock boosted motor you don't have the throttle secondaries so you end up with the oil and carbon deposits on the rotors of the blower and coating the intercooler. So at some point you need to remove the blower and clean the intercooler.
Last edited by twinskrewd; Jan 2, 2015 at 10:59 AM.
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I think the catch-can can work to some degree and provide the ability to check how much of an issue there is in a tattle tale kind of way. I also don't really know what it would take to get the check valve solution to work. It seems like it could work under some conditions like a 1/4 mile run but have the same issues in a Texas Mile run.
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For the Whipple SC it appears that the PCV is in the intake track before the intake charge is compressed, so I would think that it would perform normally except for the extra pressure in the Crank Case (CC) induced by forced Induction (FI) blow-by. I don't think there is any FI pressure getting into the CC directly. Only what is leaked passed the rings via the combustion process, so the pressure would be the same as it is entering the CC, just a larger volume of it and with a larger volume and the same size hole to escape from, more pressure.
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BTW, I post these queries/suggestions not because I don't know an answer, but because I am constantly seeking for the best answer. The Socratic Method, I suppose?
Last edited by MeanGene; Jan 4, 2015 at 03:34 AM.
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N/A, Twin is right. No need to change anything. An ounce or two of oil IS negligible. Blown? TWO QUARTS down is a PROBLEM. Especially when you are WOT in the turns and the oil is forced away from the oil pan. What will you do when the RED light comes on? Go empty the catch can and put it back? If you say so... There will always be some amount of oil build up in the intake, normally it does take time to start causing problems. But we are talking blown engines here. It does not matter what blower you are using. It does not matter if it is a Ford, GM, or MOPAR. This WILL be an issue. Boost means MORE blowby than the stock PCV system is designed to handle. In many cases, tuners will tell you this condition is negligible. Others will tell you that after 40 YEARS of GM experience (In THIS case IS relevant, not not applicable), that a catch can is the SOLUTION when it just prevents losing the oil by spraying around the PCV valve or through other leaks. JBravo had his PCV valve blowing out. This is basic aero and fluid dynamics. Something many do not get out of an automotive technical program. My education includes Thermodynamics, aerodynamics, fluid dynamics and hydraulics. And again, there IS NO FLOW without a pressure DIFFERENTIAL. The oil being picked up is a collateral issue of the problem, which is air flowing through the CC. When you boost the CC, this makes the problem worse. Correction - $60-400 for a catch can only to capture the symptom of the problem, only to have to maintain it and put the oil back into the CC. We have seen the CC lose TWO QUARTS in a MONTH without addressing this issue. And remember, I am dealing with three offline right now that are having this problem. If only they would come forward and share their experience. Laurence? John? Anyone want to share their experience with catch cans?