PVC Catch can system.... Final conclusive answer
#201
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i ran each of my valve covers to 2 port catch cans. one on each side, the inlet comes from the valve cover, the outlet runs to my exhaust. When I rev the engine at idle with the lines unhooked, I can feel a substantial vacuum getting pulled from the exhaust
#202
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Is it possible for the exhaust to have back pressure and push exhaust into the valve cover?
#203
Launching!
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yup, its got one way check valves, but I dont know how necessary they are. the ports into the exhaust are at like a 45 degree angle, so it pretty much works all on venturi effect
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Yep, put the evac tubes in the exhaust at a 45* angle. Atleast a few inches into the collectors IMO so there's no chance of reversion. On our jetboats we usually have them atleast 5-6" after the collectors.
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I used to sell them. I dont any more but am looking to have them made again. I have seen a big push to have them offered again. I am working with two machine shops now to see what we can do.
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Here is how I ran mine:
![](http://www.ls1fc.com/main/1988/enginebay/IMG_4017.JPG)
![](http://www.ls1fc.com/main/1988/enginebay/IMG_4019.JPG)
-10 AN between the valve covers with a -12 AN running to a Moroso breather. The 10 AN lines had bungs welded into the covers (I milled the covers to sink the bungs in flush) and the -12 AN is where the factory PCV port was (rear of driver's side cover) so the baffling is still in place. No discernible oil in the intake at 6-7 psi of boost, we'll see how it handles 15-18 this summer.
Oh, and FWIW, the fuel pressure regulator and return line have since been relocated to somewhere better.![Winky](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_wink.gif)
edit: In more detail:
![](http://www.ls1fc.com/main/1988/may09/IMG_3985.JPG)
-10 AN between the valve covers with a -12 AN running to a Moroso breather. The 10 AN lines had bungs welded into the covers (I milled the covers to sink the bungs in flush) and the -12 AN is where the factory PCV port was (rear of driver's side cover) so the baffling is still in place. No discernible oil in the intake at 6-7 psi of boost, we'll see how it handles 15-18 this summer.
Oh, and FWIW, the fuel pressure regulator and return line have since been relocated to somewhere better.
![Winky](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_wink.gif)
edit: In more detail: