jknc90 Posted March 12, 2009 Share Posted March 12, 2009 So the verdict is the block plug is fine as long as the valve cover is vented? Quote Link to comment Share on other sites More sharing options...
Edz280zx Posted March 12, 2009 Share Posted March 12, 2009 Apparently so... Quote Link to comment Share on other sites More sharing options...
Cobra_Tim Posted March 12, 2009 Share Posted March 12, 2009 So the verdict is the block plug is fine as long as the valve cover is vented? I’m not 100% convinced of it... I’m not sure exactly how much volume were talking about so IMHO the single valve cover vent COULD be a restriction. So unless someone who KNOWS otherwise posts from experiance (I want one last post from BRAAP)... I’d consider the case still very much open. Quote Link to comment Share on other sites More sharing options...
Edz280zx Posted March 12, 2009 Share Posted March 12, 2009 Mines been like this for over a year...but then I drive it maybe 5000 miles a year. Quote Link to comment Share on other sites More sharing options...
Cobra_Tim Posted March 12, 2009 Share Posted March 12, 2009 Mines been like this for over a year...but then I drive it maybe 5000 miles a year. My situation will also be different... My motor won’t see much time below 4 grand and live most its life between 4 and 7 Quote Link to comment Share on other sites More sharing options...
Edz280zx Posted March 12, 2009 Share Posted March 12, 2009 This is true...I wouldn't think it would be a problem..not sure tho? Quote Link to comment Share on other sites More sharing options...
bradyzq Posted March 12, 2009 Share Posted March 12, 2009 (edited) Well, you could vent the block breather too, with a bigger K&N. That's the way mine has been for years. Small K&N breather on the valve cover, and a bigger one on the block breather pipe. Of course, now you have two filters to clean instead of one. Another option is to use some kind of exhaust evac system, like the old drag racers. That would give you a greater pressure difference across the rings, and maybe a bit more power as a result, if it's legal in your class. Basically, you are using exhaust flow as your source of vacuum, instead of post-throttle intake manifold. Edited March 13, 2009 by bradyzq corrected type, evap to evac Quote Link to comment Share on other sites More sharing options...
Cobra_Tim Posted March 12, 2009 Share Posted March 12, 2009 Well, you could vent the block breather too, with a bigger K&N. That's the way mine has been for years. Small K&N breather on the valve cover, and a bigger one on the block breather pipe. Of course, now you have two filters to clean instead of one. Another option is to use some kind of exhaust evap system, like the old drag racers. That would give you a greater pressure difference across the rings, and maybe a bit more power as a result, if it's legal in your class. Basically, you are using exhaust flow as your source of vacuum, instead of post-throttle intake manifold. Both are illegal in SCCA... If the a single vent is ample for all evacuation then I run just the valve cover breather... I may even enlarge it. If its not big enough... then I run the block breather unplugged(which I taped to 3/4 NPT) then it goes to the catch can, which is vented. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted March 12, 2009 Administrators Share Posted March 12, 2009 So the verdict is the block plug is fine as long as the valve cover is vented? Calling it “fine†is relative. Yes the valve cover breather alone, all by its ones-ie should be more than adequate ventilation for the crank case, but it is still not ideal. I’m not 100% convinced of it... I’m not sure exactly how much volume were talking about so IMHO the single valve cover vent COULD be a restriction. So unless someone who KNOWS otherwise posts from experiance (I want one last post from BRAAP)... I’d consider the case still very much open. My thought on this is, if there is enough blow-by coming past the rings that the valve cover breather is a restriction causing pressure to build in the crank case, that engine has issues to the point it needs to be removed from service and torn down, i.e. busted rings, hole in piston, collapsed rings, etc. There should never be enough blow by past the rings that the valve cover breather alone would be a restriction to the evacuation of the crank case, to the point pressure would build behind it. Quote Link to comment Share on other sites More sharing options...
josh817 Posted March 12, 2009 Author Share Posted March 12, 2009 Thats true. I had slight smoke coming from my vent when the motor was fresh. I don't think it does it anymore but if you twist the filter so the bottom faces up you can see a bit of oil ready to drip off of it, plus my manifold isn't pretty anymore either. Run a catch tank so it collects all that goopus. I know the customer I have right now who races a Spitfire for CVAR use to blow by a quart of oil after two races. He would dump his catch tank out into the used oil bin and would spend like $100 on oil since he runs the $8/quart stuff. It was pretty messed up... haha Quote Link to comment Share on other sites More sharing options...
woldson Posted March 13, 2009 Share Posted March 13, 2009 How about just a K&N filter on the valve cover (for intake) and run the crankcase into the exhaust at an angle to help pull air threw the engine? Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted March 13, 2009 Share Posted March 13, 2009 How about just a K&N filter on the valve cover (for intake) and run the crankcase into the exhaust at an angle to help pull air threw the engine? That would work also. I'm going to do just that on my RB. I bought a crank case evacuation kit off Summit, that comes with the proper 1 way fittings to weld into your exhaust, which pulls a vacuum as you run the engine.. Quote Link to comment Share on other sites More sharing options...
thetremendoustim Posted July 17, 2009 Share Posted July 17, 2009 wow this thread (braap guy) answered all my PCV questions, however I have just one. I've been convinced that its in the best interest of my old rings, and overall engine stress to plumb the PCV back on the intake (N42 with turbo = but i already have a 90* fitting) but I dont want to have to find a new hole to vacuum the valve cover to, so would it defeat the purpose to have the block go to the intake but leave the valve cover open? Its baffled, so i think that will help in answering the question... Quote Link to comment Share on other sites More sharing options...
thetremendoustim Posted July 17, 2009 Share Posted July 17, 2009 Okay so after thinking about it all night and morning, I guess securing on the crank to intake and leaving the valve cover open is essentially pointless since its a huge vacuum leak. Where can I put the valve cover to considering I'm a l28et without a AFM boot with one of those plugs on top. I am thinking route it to the j-pipe/AAR via ANOTHER pcv valve and a 3way connector that makes sense right now to me at 10:14 AM. let me think more about it. Quote Link to comment Share on other sites More sharing options...
HowlerMonkey Posted July 18, 2009 Share Posted July 18, 2009 If you're not running pcv to a vacuum source, a little filter on the valve cover could become fouled with oil and effectly clog causing high crankcase pressure. It should go to a catch can sort of device that allows the oil vapor that ends up liquifying in the piping to pool in a low point and have the filter at the highest point so it doesn't receive liquid oil to the element. Quote Link to comment Share on other sites More sharing options...
woldson Posted July 18, 2009 Share Posted July 18, 2009 Too bad foldgers comes in plastic containers now......... Quote Link to comment Share on other sites More sharing options...
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