Guest JAMIE T Posted May 23, 2005 Share Posted May 23, 2005 Hey gang, I'm prepping my valve covers for finishing and want to know what you have done with your valve cover vents. Since neither of the engines I bought had these connected to anything, it leaves me wondering. I am sure they would normally go back to the intake, Is that correct? I was looking at JT's '25 and he has one vented to atmo and connected to the other one, and the one closest to the intake is plumbed to the intake. It looks like it's fine. I have seen other similar style vents go to a single tank with a breather on it. The Titan Motorsports Supra is done this way. What is the reason for that? Also on the finish of the valve covers. I'm TORN. At first I was going to do it body color(pearl orange), then I was thinking chrome plating, then I was thinking gun metal(anthricite metallic) as a contrasting color. All my suspension is Anthracite. Quote Link to comment Share on other sites More sharing options...
Zhadman Posted May 23, 2005 Share Posted May 23, 2005 My understanding is that one line (of the 3) runs from the PCV valve to the passenger side valve cover. The second connects the two valve covers, and the third runs back into the intake tract (pre-turbo). IIRC you can: A) Disconnect the hose running to the intake and instead run that line to the catch can (that vents the gases to the atmosphere). Run a line from each valve cover to the catch can... blocking off the port that ran to the intake. Now... I have heard that it's not a good idea to re-use the oil that is collected in the can because it might be contaminated by the blow-by gases. This might be fiction, though. As for the finish of your valve covers... I had mine done the color of the car (red) and wasn't happy with the finish or the color matching. I think I'm going to have them stripped and done in my primary accent color (gold). My engine bay is blacked out (i.e. satin black finish) and I think the accent color will set it off. You're painting your engine bay, right? I think the anthracite would look awesome! I like contrast, though. Quote Link to comment Share on other sites More sharing options...
Guest JAMIE T Posted May 23, 2005 Share Posted May 23, 2005 Engine bay will be car color. Pearl orange. I have two sets of valve covers. So, maybe I'll do them both ways and see what looks best. Quote Link to comment Share on other sites More sharing options...
johnc Posted May 23, 2005 Share Posted May 23, 2005 Be careful with crankcase venting. A simpe solution is two lines to a catch can with a filtered breather on top of the can. Locate the can in a place where if it overflows it won't start a fire. A PCV based system is a better solution for a street car. Its common for the crankcases on the forced induction engine to get pressurized under boost from ring and valve seal blowby. A fixed orific PCV valve only opens under vacuum so prologed boost will stop any crank venting. When the PCV valve does finally open it tends to dump a lot of oil mist (and some oil if not properly designed) into the intake tract. There are variable flow PCV systems (Toyota is one) on new vehicles that work correctly based on blow-by production (small orific opening at idle, large opening under load). Quote Link to comment Share on other sites More sharing options...
Guest JAMIE T Posted May 23, 2005 Share Posted May 23, 2005 So that would explain the catch can on the Titan Supra. Lots of boost, everytime it makes a run, it's a drag car only. Thanks John, and Zhad. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.