Catch can set up

Hey all,

So I'm trying to work out how I'm going to set up my oil catch can and get both pcv valves. My catch can only has 2 ports so I was thinking of t-ing the hoses from the valves to the can then t-ing them again to the intake.

I don't think there should be any problem because it's not like the crank has different pressures on either side (right?). But just thought I'd check with the wise elders first.

 

The valves are installed in the plenum so running from the PCVs to the intake wouldn't be doing much useful. The most common option in fitting catch cans is to simply block off the ports in the rear of the passenger side exhaust cam cover that feed the PCVs and plug the PCV ports on the plenum then run the front cam breather pipes (in the intake cam covers near the throttle bodies) and either run both of them to a vented can or tee them into a can and return to one or both intake pipes (pre-turbo). Vented cans need to the crank case system to be completely isolated from the intake due to the AFM so you can't run a vented can to the intake pipes or use a vented can with the PCVs installed.

Although this generally 'works fine' it does mean that you no longer really introduce fresh air into the crank case and draw volatile combustion products out and through the engine for re-burning and exhaust. This means to some degree you are accelerating the degredation of your oil as it dilutes and acidifies.

There are guides around for making new ports in the intake cam covers for the PCVs which are higher and much less susceptible to being splashed with oil and you could use these in conjunction with a sealed can between the front cam cover ports and intake pipes for a better system.

 

The front breathers being on the intake cam cover? Has someone got a picture, that would be mighty helpful.

 

Yep front of the engine, the hose in this picture joins the cam covers to the intake pipe, remove that hose and replace it with you catch can set up. One for each side, both sides teed together or even do one side and plug the other should work.

 

Will that still beathe sufficiently rob? Im planning on running rear vents to catch can then pcv, then seperate can for inlet cams.... or is this just way overkill likke i keep thinking

 

I'm doing exactly the same as Rob suggested in the race car and not seeing any issues. I'd run both sides though rather than blocking one side, just to maintain balance. May or may not make any difference.

 

yep front covers is sufficient .

use a decent catch can that breathes ,I run a twin filter catch can on mine slightly bigger than the 10an hoses (filter outlets)

30psi+ boost ,big horse power no problem

.

 

I also was running it the way rob said for many many years . And I had no problems. I blocked/welded everything shut as well. . T two into one straight to the can . End of story. Acually I still have my old set up . That I won't be using at all.

 

That reminds me. I need to set one up before going out onto the track again.