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Old 09-22-2005, 09:27 PM
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Blowby

Doc here,

How much blowby do you have? a little is a common byproduct of combustion...How new is the engine?

Is it possible the rings have not seated, or seated properly? how did you break it in?

First if you eliminated the PCV for straight vacuum your heading for trouble..that blow by, over time, will turn to straight blue smoke out the pipes, fouled plugs and it will run like crap in a can...as you will be sucking straight oil into the induction system and burning it.

The valve is designed to be a one way valve, and shut off as soon as the vacuum is relieved (off idle, acceleration) when the vacuum is low AND oil pressure is high. Put the valve back in..or block it off altogether..Plus even with the restriction , it can't be too good for the vacuum volume.

Next, Was the Valve cover cap on the opposite Valve cover vented? If not therein lies your problem...The PCV MUST travel across the engine to pull blowyby out..If it's blocked off (no breather ) it will only breathe until the pressure is equal at the valve and crankcase, then become a "Vacuum canister" that will blow gaskets over time.

Put a vacuum gauge on the tap and see what you actual vacuum pressure is..should be a STEADY 17 to 20 In Hg at idle and decrease with throttle..(unless you have a real Lopy Cam..)

Baffles, as Henry Said, are important, especially with an engine that has an overactive top end oil system..and "Shortie Valve Covers" you can get a breather cap with a baffle installed in the cap (which is nothing more than a cap with a steel wool like substance inside of it..) but on the PCV side you should have a Valve cover baffle, or baffled grommet.

Try that, see what transpires..

Doc
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