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Old 05-29-2004, 04:57 AM   #1
TwinTurbo
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Join Date: Sep 2003
Location: The Netherlands
Posts: 994
Quote:
Originally Posted by zzChevy
Right. So on one side you have the PCV to carb, the other side should be connected to the air cleaner directly from the valve cover. Member the old stock air cleaners we used to have on these things? Had a filter within a filter. Same thing should apply here.

What I am getting at is specifically my idling. I could not get it right no matter what i tried. Until I closed the system. Its close to perfect now.

Other than my damn column woes.

Granted, it might not work on everyones setup.

Thanks for reading
What a bunch of misinformation here. The PCV is a vacuum leak yes but your carb/injection system is calibrated to have it, it's just a different idle setting with the PCV system in place. It does not matter one bit where the air is going through, being a breather or carbon filter like on stock. As long as the air is filtered so that no unfiltered air enters the carb.

You are not venting to the atmosphere with a breather, there's no venting taking place, air enters through the rbeather, circulates through the crank case and is sucked into the carb. If you remove the PCV syste, and run 2 breathers or a collector scavenge/evac system (I have that on my other engine) you will notice idle rpm on the carb will be down and has to be adjusted.

Getting back to the stock system, the stock system hooks the pass. side valve cover to the air cleaner with a small tube and there's a carbon filter in the air cleaner housing (that's in most stock systems, I think that's what you are referring too right??) If you look closely the air OUTSIDE the filter is NOT fitlered, that's the case with the air going through the carbon filter too. The little tube is a cheap solution so the factory didn't have to resort to breathers. The carbon is there however for a reason, it's there to take up fuel vapors (carbon is porous and bonds almost anything, that's why you have to swallow the norrit stuff in case you poisoned yourelf with something like bleech or so) The carbon filter makes that no fue vapors enter the crank case via the tube after engine shut down. Same reason why many stock systems have a carbon canister on the fuel vent line from the tank, the canister gets sucked empty at engine start up when the purge solenoid engages. If it were not there fuel vapors could enter the crank case when the engine is shut down and mess up the oil. Oil develops acids and this can ruin the engine internals.
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