I just wanted to say this is one of the most if not THE most confusing thread I have read. And I read the entire thread -____-

BUT I need your help!



I am planning to do this set up with FI:

1) PVC and the hose to the plenum stays the SAME!
2) Oil catch can with two huge breather on top AND 3 welding AN bungs on the can
3) one hose from the driver side crossover to the catch can and another from the passenger side crossover to the catch can. And the last hose come from the driver side rear ventilation to the catch can


Please let me know what you think and will this be safe and ok. I got my car tuned recently and really need an oil catch can.

 

this is such a basic concept,what is confusing you?

you cannot leave plenum vacuum on a vented catch can. Unless you pull the valve covers and drill out the vents (not just the PCV, the cover itself is more restrictive than the PCV), those catch cans are nothing but show. Sure you might catch some vapors, but you are missing the point of reducing pressure.

The ID of the vent holes, esp the PCV is less than 3/16ths. thats a tiny -3AN sized hose. Those holes need to be opened up to at least 5/8" (-10AN).

Both my VC's are drilled out to a little more than 5/8" ID with -10AN lines. Look at any car that has a proper catch can setup (2JZ, V8s...), and you will notice at min -10AN lines from each valve cover.

 

I will have a -10 on each of the front vc (crossover) and a -12 will fit over the rear driver vent.

your saying i still need to drill out the pcv?

 

No point in a big line if the valve cover has a teeny weeny hole. Not to mention that the PCV can let boost back in to the crankcase and serves as a further restriction for out flow. Yes, drill it out.

 

I was planning to drill out the VCs

So is there a proper set up with an oil catch can? Im throwing a lot of white smoke when tuning on the dyno.

What should i do? there is so many people saying so many different things thats all, just need help on the right way i should do it. I have a single front mount turbo set up.

Thanks in advance

 

some are saying drill the pvc and some are saying to leave it a lone. I just want to know the proper way to prevent pressure and to include a catch can if needed.

 

Drill out the PCV. Have both the driver's side and passenger side go to a catch can and vent to atmosphere. Cap off the intake manifold port that used to connect to your PCV. If you want immediate results, clean out your IC and plenum from all the oil you've put in there previously and you'll be all set (or you can just let it burn off).

Done.

PS. You may not need to drill out the VCs. Don't use thin hose, long lengths of hose, or hose that cannot take the heat (collapses). Best escape route for gases is a breather right on the nipple for each VC.

 

Did you want me to use the front vents from driver and passenger side VCs to go to the catch can? where the crossover hose use to be?

what about the rear driver vent? hook that up to a breather? also hook up a breather to the PCV correct?

thanks again for your help and time!

 

I would leave the center cross over hose untouched. No need to mess with that and those ports although I suppose if your blowby gets really bad, you could vent those too.

Yes, just drill out PCV and put breather on that nipple (3/8") and on rear driver's side nipple (5/8") and you cannot go wrong. All the other solutions listed in this thread are for tweaking this basic set up (depending on if you have a pull through MAF setup, fumes at idle, blah blah blah).

 

Oh yeah, don't try to pass emissions testing like that, by the way. The driver's side breather won't be visible, but cap off the passenger side pcv so the inspector doesn't flag it (and don't boost it like that - fine under vacuum).

 

wait, dont i need to use those ports on the cross over to have it hooked up to the catch can and vent to atmosphere? like you stated before?

 

Leave the cross over tubing untouched.

The passenger side nipple to breather.

The rear driver side nipple to breather.

I never stated anything different (today).

 

so this is how i should do it with an oil catch can?

 

this way wouldnt be ok?

 

No drilling required. The center posts are not designed for trapping oil. Leave those be unless needed.

 

I thought this whole time you were telling me to drill the PCV. I must be going crazy... :/

 

Oh jeez man. Yes, drill the PCV - the white valve thing so the spring drops out of it. Unscrew the PCV, drill from behind with a bit that is just smaller than the size of the nipple (the drill bit should fit easily through). The spring and valve will drop out. Screw the PCV nipple back in. Done.

Do NOT drill the valve cover like you have depicted in the first pic to add a fitting.

 

^^Raj has the patience of saints

 

have you ever pulled the PCV out? The hole between the pcv and the VC is smaller than what you can drill the pcv out to be.

If you are truly wanting to reduce crankcase pressure, you cannot expect to do so thru a 1/8th hole in the VC's

both my VC's are drilled out to 5/8" using 1/2" ID hose venting them.

Cars that make real power that worry about crank case pressure need real vents

^^just imagine exact same setup on our cars with the left hose coming from the PCV area, and the right hose coming from the back of the VC.

Thats how you setup at catch can.

 

thank you for helping. i was confused because at first you only replied saying "No drilling required." on the image which included only the PCV.