Results 1 to 9 of 9
  1. #1

    Join Date
    Oct 2011
    Location
    Foley Alabama
    Posts
    127
    +1
    5

    One more catch can post

    Just watched a vidio from Kevin Shaw on mounting a Riva catch can, and left scratching my head. When we added a catch can to a Chevy v8 or a v6 the can was always installed between the pvc valve and the intake, to catch the oil going into the intake manifold.
    when the Rive is installed by-passing the pov valve, don't you create a positive crank case pressure?
    Should the catch can be installed between the pov valve and the intake hose to the supercharger. This will create a negitive crank case pressure .
    Don.t see any advantage the way Riva has there can mounted. But, what do I know. Happy Thanksgiving Jerry


  2. #2
    Team Bilford's Avatar
    Join Date
    Jul 2009
    Location
    Fort Worth, Texas
    Posts
    1,337
    +1
    194
    The TOPS valve is the PCV in this application. The line runs directly to the can from the TOPS. The hose that you plug is where the vapors would have been reintroduced into the induction system.

    The line to the can is positive pressure from piston ring blow by into the crank case.

  3. #3

    Join Date
    Oct 2011
    Location
    Foley Alabama
    Posts
    127
    +1
    5
    So what is the advantage or dis-advantage of having neg. or positive crank case pressure? Why have a catch can, just put a air filter on the end of a hose.

  4. #4
    Team Bilford's Avatar
    Join Date
    Jul 2009
    Location
    Fort Worth, Texas
    Posts
    1,337
    +1
    194
    Quote Originally Posted by conroe View Post
    So what is the advantage or dis-advantage of having neg. or positive crank case pressure? Why have a catch can, just put a air filter on the end of a hose.
    You could put a breather filter on the end of the hose, but you would blow oil mist all over the engine compartment. The can and its baffle material removes most of the oil from the vapor and then it vents to the engine compartment.

  5. #5

    Join Date
    Oct 2011
    Location
    Foley Alabama
    Posts
    127
    +1
    5
    What would happen if the catch can was mounted between the tops valve and the intake hose to the supercharger? This is the norman postion on a car.

  6. #6

    Join Date
    Sep 2017
    Location
    London UK
    Posts
    340
    +1
    54
    Quote Originally Posted by conroe View Post
    What would happen if the catch can was mounted between the tops valve and the intake hose to the supercharger? This is the norman postion on a car.

    I think the issue with ski verses a car is ....lets say the catch can was half full (we're all lazy sometimes) if you hit a good wave it might be possible for the intake to take a big chug of the cans contents, this going through the charger ,inter-cooler and finally the engine is not a good scenario, this is unlikely to happen in a car. As you mentioned earlier negative crankcase pressure is desirable but I guess it's a case of the lesser of two evils as to how it's done the way it is.

  7. #7
    1tommygunner1927's Avatar
    Join Date
    Apr 2007
    Location
    Houston, Texas
    Posts
    9,460
    +1
    2,769
    There are "catch cans" and air/oil separator cans:



    Catch Can......



    Air/oil (baffled) separator cans:


    The Riva catch can vents to atmosphere, the baffled air/oil catch can vents to the intake. Both need to be emptied of gas/oil.

  8. #8
    Team Bilford's Avatar
    Join Date
    Jul 2009
    Location
    Fort Worth, Texas
    Posts
    1,337
    +1
    194
    Quote Originally Posted by conroe View Post
    What would happen if the catch can was mounted between the tops valve and the intake hose to the supercharger? This is the norman postion on a car.
    There have been a couple of guys that have run the line back to the intake fitting. It will slow, but not stop the oil mist from coating the IC and SC. If you want to run a true separator, it might be ok.


  9. #9
    1tommygunner1927's Avatar
    Join Date
    Apr 2007
    Location
    Houston, Texas
    Posts
    9,460
    +1
    2,769
    Quote Originally Posted by Team Bilford View Post
    There have been a couple of guys that have run the line back to the intake fitting. It will slow, but not stop the oil mist from coating the IC and SC. If you want to run a true separator, it might be ok.

    The baffled air/oil cans are much more expensive than a "catch can".

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Replies: 11
    Last Post: 01-13-2017, 06:37 PM
  2. Replies: 1
    Last Post: 01-03-2015, 08:52 AM
  3. Replies: 7
    Last Post: 06-16-2012, 02:08 PM
  4. Catch can or not to catch can that is the question?
    By 97GSX in forum 4-Tec Performance
    Replies: 2
    Last Post: 12-07-2009, 04:11 PM
  5. Continuation: To catch or not to catch can
    By HOSS in forum 4-Tec Performance
    Replies: 13
    Last Post: 05-01-2006, 03:19 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •