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You're not alone. Not many people seem to understand that a PCV isn't just big brother forcing emissions **** on us.

Again though, race car vs. street car. People know more about race cars than street cars because it's more fun. But a race car driven on the street still has street car problems.
Not many people understand that smog, EGR, PCV, and the charcoal canister vent are completely different systems either. It's all "emissions junk". Some of it has benefits and doesn't do squat if you take it off.
 

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I should say that, while I apparently wanted to get on a PCV soap box, my experience is that A LOT of fuel in the oil is due to dumping fuel at idle for some reason. What did your plugs look like? If the plugs were wet then no amount of PCV can fix that. I had that happen to me once. Carb issue. Junk on the needle or stuck float causing fuel to come out the overflow down the carb. It idled for awhile that way before I figured it out. My oil had tons of gasoline in it and the plugs were hopelessly fouled. Oil change. Plug change. Carb fixed. Problem solved.

I have EGR and PCV on my turbo 4cyl. The PO had removed the EGR and charcoal cannister, left the PCV. I added the EGR back when I switched back to a stock intake manifold. Didn't bother with the charcoal cannister. It's somewhere in boxes but my battery is there now anyway.

My Mustang is 1965 and thus just has the PCV.
 

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Not many people understand that smog, EGR, PCV, and the charcoal canister vent are completely different systems either. It's all "emissions junk". Some of it has benefits and doesn't do squat if you take it off.
All of it is there for a reason. None of the emissions stuff hurts performance, except the catalytic converters if you get over a certain HP level, mainly due to being a restriction to exhaust flow. Although I will grant that there is some small benafit from the removal just from weight alone, but that is marginal at best. The charcoal canister's job is to prevent fuel vapors from entering the atmosphere (ground level ozone), the PCV prevents fuel dilution of the oil and prevents fuel vapors from entering the atmosphere. The EGR reduces combustion temps to lower NOX emissions. None of these things really are a detriment to performance. To this day, modern EFI engines still use EGR, PCV and A EVAP system (including a charcoal canister) and still make impressive HP. A 5.0 Mustang makes 480 HP even with these items. That is almost 1.6 HP per CID N/A. Obviously the "emissions junk" is not hurting anything.
 

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Old school tech here,,,, I had a 440 six pack dodge " back in the day" that would eat up a set of spark plugs every 700 miles or so.. The car would start to miss and run poorly... It would always dump fuel into the oil when this would happen and I had to change it...
Wheel Tire Car Automotive parking light Vehicle
 

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So what was the cause ?
I could only guess at this point.. When the 2 or 3 plugs didn't fire the fuel it must have by passed the rings.. I was 17-18 when I had this car and my part time job ( during high school) barely paid for the gas that thing consumed..
 

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Contaminants will only be drawn through the PCV valve under vacuum. It can be more complex in a boosted application if you have positive manifold pressure at idle. If you have a turbo, not a problem, you just need the right valve for a boosted application. With a centrifugal supercharger, do those boost at idle normally? With a roots blower? Honestly I don't know. You need a vacuum pump in that case I think.
I’m not disagreeing with you about the benefits of PCV systems and I agree they should be used, but there is no engine that has positive manifold pressure at idle.
 

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Have you done a leak down on the engine?

What's the condition of the rings?
 

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I’m not disagreeing with you about the benefits of PCV systems and I agree they should be used, but there is no engine that has positive manifold pressure at idle.
My bad. I thought with a roots blower this was sometimes possible. What about a diesel? They don't have a throttle body. I thought turbo diesels could have positive manifold pressure at idle too.
 

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My bad. I thought with a roots blower this was sometimes possible. What about a diesel? They don't have a throttle body. I thought turbo diesels could have positive manifold pressure at idle too.
A roots blower would have a tough time making boost through closed throttle blades. Diesel won’t have positive manifold pressure at idle either.
 
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