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PCV valves

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Cool53:
They are not all the same.
A ache vette in 1976 had a PCV valve that only flowed .7 CFM. Normal Chevy V8's flowed 2.8. The V8 valve placed in a ache vette would not really affect how it ran, but would empty the crankcase in no time. Once they realized they had a problem chevy had the Chevette units plastic T cast with pink plastic to make it stand out. The aftermarket did not.
There are thousands of different PCV valves, many look alike. But they flow differently, open at different throttle amounts, and close differently. Spring rates are different, valve shapes are different, internal passage sizes are different.
For this reason it's better to use a factory (Delco, Ford, Mopars) valve that is close to what yo are running, or even better, a Moroso crankcase pressure control valve. With this valve taking the place of the breather or breather tube and adjusted properly to maintain a crankcase pressure of 5-8" of vacuum, you keep the rings pulled in slightly at cruise, reducing drag, you make valve seals, rear main seals, and front crank seals that may not be all that healthy work a lot better. You now don't really need a PCV because The Moroso part is controlling air flow. These pieces work great. The next step up from that is an all out vacuum pump, but if you aren't racing you don't need that. If you race once in a while you may want to T an aspirator from the header collector in, but make sure to place a check valve, like from an AIR pump into it so the Moroso valve will still work.
Simple things make big differences.

EDNY:
GOOD STUFF!  THANKS

Cool53:
Hi Ed,
Are you interested in any Tuned Port Parts? I have a bunch of stuff I will probably never use. Jef

EDNY:

--- Quote from: Cool53 on January 03, 2014, 07:01:19 PM ---Hi Ed,
Are you interested in any Tuned Port Parts? I have a bunch of stuff I will probably never use. Jef

--- End quote ---

Let me know you what have, I lean toward to the 90-92 speed density stuff and have a decent collection of TPI parts..both MAF and SD.

Also made a couple of TBI harness's and about to try my 1227747 ECM 24 to 28 pin EPROM conversions for the first time!

Ed

Cool53:
There's a guy that rebuilds injectors here in Fitchburg, MA, Hurst Fuel Injection. Does a great job, gives you all the before and after numbers. Gets about $125 a set of 8.

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