Authors: TurboGLH
Last modified: 12-21-05
Stage: 60%
Type: How To
------------------------
Edit 7/31 11:20am I've been discussing with people the advantage of tapping into the airbox/cai to use the vacuum in the system to help draw down the crankcase. I'm posting a writeup on how I think chrysler was thinking when they designed the stock system as well as linking to a post by DodgeZ that shows how to use the vacuum from the airbox without getting oil in the intake/intercooler.
I Think that chrysler set the system up the way they did for two reason, one to provide some vacuum assist on the pcv and also for enviromental reasons, once the pcv is blocked due to the car being in boost the presure has to go somewhere and they couldn't just let oil vapor out into the atmosphere, the epa would have had their ---. So they put it back into the intake system at the only point that wouldn't be pressurized at that point. Better to send oil into the turbo and intercooler and eventualy into the intake to be burned (like it would normaly). The setup I listed doesn't provide for any active evacuation, but the actual draw from the stock setup is not that great. The design could be modified to tap into the intake, most people who've made cai's dont' have the nipple on their system as they want to avoid the oil'd down intercooler issue.
The design below could be reversed to tap into the airbox, with the pcv on the pass. side and the drivers side connected to the airbox. Please read both threads and make a decision based on your application.
http://boostedmopar.com/forums/showthread.php?t=108
----------------------------------------------------------------------------------------------------------------------------------
I case you didn't know the pcv system on TD's sucks. It has to breath and vent from the same nipple on the valvecover. The system works poorly at both task's and was changed towards the end of the run, at least for TBI cars.
Materials: Valve Cover, new pvc valve, two (2) pcv elbows from a tbi car, one k&n filter p/n 62-1010, a new pcv to intake hose, extra nipple from another vc if using stock cover and a cap for the nipple on the air box (if your still using the stock intake system).
Step 1 Valve Cover
Now is a good time to step up to a one piece seal vc, the cast tbi cover described below uses it along with later turbo covers, no more replacing end seals and RTVing the crap out of the cover to seal it. As long as you don't pinch the seal you can use it over and over.
If you don't care if your car says turbo on the vc then you can start searching the J/Y's, your looking for a TBI car (most likely 92+) with a cast vc instead of the stamped steel one. Now look close at the passenger side of the vc, it will have another nipple identical to the drivers side one. Photo Below....
Grab it and the oil curtain underneath and move onto step 2
If you like to show off, or if you have a really nice/powdercoated vc then you can modify you existing cover by drilling it out on the passenger side and pressing in a nipple from another cover. It should be a press fit and use ChryCo grey RTV on the end to be pressed in.
NOTE: ON A TURBO VC THERE IS A COVER BOLTED TO THE INSIDE OF THE VC OVER THE PCV PORT. WITH SOME STRATEGIC GRINDING AND A RESEAL YOU CAN GREATLY REDUCE THE AMOUNT OF OIL THAT MAKES IT TO THE PCV VALVE. UNTIL I'M ABLE TO TAKE PICTURES I'M GOING TO LEAVE THIS STEP OUT.
Step 2 PCV System
1) Remove all the old pcv parts. If using a modded Turbo VC, skip to step 3
2)If using the TBI cover remove the #1 and #2 cam caps, remove the old oil curtain and replace with the TBI one, replace and retorque the caps.
3)Install your the new/modified cover.
4) Place a tbi elbow on each nipple, now insert the k&n filter into the passenger side elbow and place the pcv valve into the drivers side.
5)Connect the pcv to the intake with your new(preferably) or the old hose. Cap the fitting on your stock air box(if applicable).
6)Step away and admire your work.
The system is now a correctly designed pcv system with seperate paths for the inlet and outlet. Please check back in the future as I'll be adding the steps to modify the vc to eliminate oil in the intake.
