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Discussion Starter · #1 ·
Anyone that is running any modified engine should know that once you change anything that affects internal airflow properties of the engine - your PCV will no longer be correct for your build. The PCV's you get at the store are all "tuned" for a stock LT1. Once you change anything that tweaks the vacuum profile. the PCV will stop functioning correctly. Lots of gearheads don't address this, either because finding the vacuum profile of a PCV is like searching for buried treasure without a map, or just simply didn't know this could be a problem. As a result, you will have issues that are commonly associated with a bad PCV. For me, the telltale sign was oil vapor leaking out of the filler hole and the breather hole in my valve covers and making the covers appear to be oily. I'd wager a guess that there were other things happening inside the engine that were indicative of a poorly performing PCV system.

I read about the ME Wagner Dual Flow PCV in Hot Rod and decided to give it a try. It completely solved my problem. The PCV isn't cheap (by a longshot), but it 100% does work. It does require tuning the valve itself, but anyone that can reasonably spin a wrench can handle it.

Just putting this out there in case someone else is chasing the same issues.
 

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Copy, Paste, Print to 3-ring = thanks. I don't experience any symptoms of a problem considering my modest adders. But I can't imagine a more all-encompassing solution where a concern exists, even if rather pricey. Just for benchcheck, had you already tried Marky's approach in post #14 here, using the 'pinhole' PCV:


BTW there's also reference to the Bosch BF414 cover vent. There's debates using it (I think about whether it upsets the vacuum equilibrium of an otherwise sealed system). But I used it before on my old FWB that had a little leaker issue at the grommet.
 

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1. As I said before, I replace that silly lil pasta elbow with a AC Delco FB131 / Baldwin SA4137 / Deutsch BF412 / Fram BA6592 / Hastings CB36 / Motorcraft FA 1118 / Purolator B23165 / WIX 66501 on the passenger side valvecover's fitting. Every 18 months, I replace #1 then #2 then #3, 6 months apart.
2. I then splice a NAPA 3299 fuel filter into the line, between the 88 Ford Tempo's breather filter and the throttlebody.
3. I then splice another NAPA 3299 fuel filter into the PCV line that goes from the crankcase to the inlet manifold.
4. In place of the Gen2 LT1 old style PCV valve, I use the Gen4 SBC PCV thing (12572717).
Have not needed to replace #4 yet, just blow it out with compressed air every 6 months.
Also want to:
1. replace the driverside valvecover with a passenger side valvecover
2. replace the silly lil pasta elbow with the 88 Ford Tempo breather baffle (as before)
3. splice a NAPA 3299 fuel filter into that line (as before)
4. make some sort of Y-connection between both valvecovers & the throttlebody
even though it's probably not needed, can't think of any reason why it would not help.
 

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In so I remember to read this later!

EDIT - Read it. As someone with a bone stock motor, with only a CAI and full exhaust, I can't imagine my vacuum profile has changed much, but I do use the car in a way that is way beyond "normal" driving conditions fairly often on the road course. However, the car still sees a lot of regular street and highway cruising miles every year, so I'd like to retain PCV function for that aspect.

Any thoughts on a valve like this for dual duty street/road course work?
 

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Apologies if I missed it, but what kind of modifications would necessitate tinkering with the PVC system?
 

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Apologies if I missed it, but what kind of modifications would necessitate tinkering with the PVC system?
Cam, mostly? Anything that changes the vacuum profile, which AFAIK, is predominantly a cam swap.

What else am I missing? Overall displacement bump i.e.e 383 CID?
 

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Discussion Starter · #8 ·
Yes, anything that changes the vacuum of the engine. Cam and displacement come to mind immediately.
 
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The yard randomly put out a 92 Pinto the other day, but it looks like there is no reason to buy used.

I've got to rebuild the PCV system on my biturbo car, so I have a feeling I may end up replicating some of it on my LT1.
 
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