Positive crankcase ventilation

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I didn't want to spend the $129 either... but it is adjustable and it works, instead of buying valve after valve at the auto parts store, and none of them are quite right...
Of course my idle vacuum is around 8". Those mild builds may not benefit from this toy.
 
clementine said:
In the beginning I was attempting to look as stock as possible, but that is impossible for my skill level at this point. I will start with a regular PCV and keep that area in mind as a possible problem. Saying that, everything on this car cant be eliminated as a possible problem. Im hoping for a good startup with trackable problems and having this conversation with ya'll has given me more insight to the small things that make a great ride.

THANKS FABO!!!! View attachment 1715813298
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That is one busy but orderly engine compartment. I believe that elevates you above a commoner.
 
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You can go buy 8 or so at autozone/..... or Whoever and experiment a bit to find your engines liking and not spend that much!
 
For low vac cams that will not operate correctly with the stock PCV, I just modify the stock PCV. I am only worried about the flow at idle. That flow area is about the size of a 7/64" hole. I gut the PCV, braze/weld in a steel disc, then drill a 7/64"hole in it. Job done & I have done many.
 
DrCharles said:
I didn't want to spend the $129 either... but it is adjustable and it works, instead of buying valve after valve at the auto parts store, and none of them are quite right...
Of course my idle vacuum is around 8". Those mild builds may not benefit from this toy.
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Mine is a tic under 6hg but I have a stone stock $1.99 PCV valve and it works just fine. But hay, it's a free country! For now. lol
 
72Duster440 said:
So cater to my dumb butt here, but what symptoms would I see if it wasn’t operating properly?
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I have never in my life had one inop from a low vacuum signal......and I've had some pretty low vacuum engines. The slant 6 I have now idles with only 6hg. It doesn't even have enough to pull in any vacuum advance at idle, hooked to manifold vacuum. lol

That said, all I've ever seen were inop from being stopped up and stuck, broken spring and all "that". I've heard some make noises like buzzing and such, but they still worked fine. Symptoms from a failed PCV valve can be excess blowby, excessive oil smoke out the exhaust, I've even seen a few puke oil from seals and such from too much blowby and crankcase pressure. Failed PCV valves can make an engine just messy and oil as heck on the outside. Seen that type thing a lot on 70s cars people just never opened the hood on and kept serviced.
 
pishta said:
EGR usually is sucked SHUT when engine vacuum is high (idle) and will open against a spring at anything off idle. then at WOT when vacuum is very low, it will shut again via another spring so you wont even notice its working. Trouble is our cammed up motors generate less idle vacuum than a stock camshaft so it fools the EGR into opening at idle and casuing a diluted crappy idle. Adjustable units will have the ability to set the idle vaccum leves as its baseline and then work off that. EGR is similar that it opens off idle. when they go bad (EGR valves) they tend to either open at idle (vacuum leak symptoms) or not open at all causing high NOx levels.
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Why would you use a egr valve on a old car or a hot rod?
 
DrCharles said:
I didn't want to spend the $129 either... but it is adjustable and it works, instead of buying valve after valve at the auto parts store, and none of them are quite right...
Of course my idle vacuum is around 8". Those mild builds may not benefit from this toy.
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Never seen this valve but I like it. I was just trying to figure something like this for my Subaru.
 
LO23M8B said:
Why would you use a egr valve on a old car or a hot rod?
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I think he was making a comparison is all.....but I can answer your question. On a mild to moderate hot rodded engine, EGR can actually be beneficial. As long as there is vacuum enough to operate it correctly, it will still function as intended.

They cool the combustion process and can pick mileage up a little.....and they DO work, contrary to what some people say. If they are in good operating condition and have enough vacuum to operate, they will work pretty well.

Now, having said all that, I'll never go to the trouble to ADD one where one is not. lol
 
LO23M8B said:
Why would you use a egr valve on a old car or a hot rod?
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To reduce NOx levels if you had to smog it. Anything newer than 65 is fair game fpr the smog police (C.A.R.B) here in Commiefornia! Can also reduce ping as it reduces the combustion temp.
 
RustyRatRod said:
I think he was making a comparison is all.....but I can answer your question. On a mild to moderate hot rodded engine, EGR can actually be beneficial. As long as there is vacuum enough to operate it correctly, it will still function as intended.

They cool the combustion process and can pick mileage up a little.....and they DO work, contrary to what some people say. If they are in good operating condition and have enough vacuum to operate, they will work pretty well.

Now, having said all that, I'll never go to the trouble to ADD one where one is not. lol
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I believe they cool the process by displaying
pishta said:
To reduce NOx levels if you had to smog it. Anything newer than 65 is fair game fpr the smog police (C.A.R.B) here in Commiefornia! Can also reduce ping as it reduces the combustion temp.
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O Ca. Now I understand.
 
pishta said:
To reduce NOx levels if you had to smog it. Anything newer than 65 is fair game fpr the smog police (C.A.R.B) here in Commiefornia! Can also reduce ping as it reduces the combustion temp.
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Don’t you mean 75 and newer?
 
Heck yeah! ...last time I checked it was STILL 65..but its has been quite a few years.....
"..Exemptions
California requires all vehicles to undergo a smog inspection EXCEPT:
  • Gasoline-powered vehicles model year 1975 and older."
Now I can buy that 75 Honda CVCC down the street !
 
pishta said:
Heck yeah! ...last time I checked it was STILL 65..but its has been quite a few years.....
"..Exemptions
California requires all vehicles to undergo a smog inspection EXCEPT:
  • Gasoline-powered vehicles model year 1975 and older."
Now I can buy that 75 Honda CVCC down the street !
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Whew, thought I was gonna have to hang a smog pump on the 410 for a minute!
 
pishta said:
Heck yeah! ...last time I checked it was STILL 65..but its has been quite a few years.....
"..Exemptions
California requires all vehicles to undergo a smog inspection EXCEPT:
  • Gasoline-powered vehicles model year 1975 and older."
Now I can buy that 75 Honda CVCC down the street !
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Do they have to have all the parts on them?
 
If they are not inspected, have at it! My 82 Mazda had to pass a visual (all smog parts intact, although I plugged the inlet of a blown vacuuum pot as there were no spares available) as well as a dyno idle/15/25 mph 'loaded' sniffer test. Darn fuel pump was weak/filter plugged and it leaned out on the 25mph load test and could not maintain the RPM window. ...FAIL!
 
pishta said:
Heck yeah! ...last time I checked it was STILL 65..but its has been quite a few years.....
"..Exemptions
California requires all vehicles to undergo a smog inspection EXCEPT:
  • Gasoline-powered vehicles model year 1975 and older."
Now I can buy that 75 Honda CVCC down the street !
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And put a 440 in it.
 
pishta said:
If they are not inspected, have at it! My 82 Mazda had to pass a visual (all smog parts intact, although I plugged the inlet of a blown vacuuum pot as there were no spares available) as well as a dyno idle/15/25 mph 'loaded' sniffer test. Darn fuel pump was weak/filter plugged and it leaned out on the 25mph load test and could not maintain the RPM window. ...FAIL!
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What’s that cost?
 
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