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Hi guys, need to put a evac. bung in my headers and need some experiences on where it will have the least interference
with floor pan, frame rails etc.

This is on a 70 Charger, 440, Hooker Super Comps. 1-7/8" 727.

Haven't had the engine in yet so don't have a feel for the best location.

I'm going to use the normal PCV to intake manifold for the street
but want to hook PCV to the bung for the track to preclude any
oil messing up my mixture.

Anyone have this set-up or can give me some guidance so I can do this once, correctly??

Thanks,

Joe

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Despite what some may say, there is no correct way to to combine an open crankcase evac system ( PCV ) with a closed system (exhaust evac system ). The exhaust evac system is not ment to be run with a full exhaust system. No matter how sophisticated it is or where you mount your evac bungs, with a full exhaust system, your check valves will be under pressure most of the time - until they burn through that is. So, the exhaust system will, for the most part, just be going along for the ride. The exception might be at idle or maybe slightly above idle, when the flow past the bungs creates a vacuum greater than the back pressure. With the PCV tied in, manifold vacuum would probably pull the check valves closed anyway. At any rate, for the most part, the exhaust evac system will be pretty much useless and the PCV system will pretty much work as designed. The bad thing is the exhaust check valves burning through - not only pressurizing the crankcase, but possibly feeding hot exhaust gas in to the intake manifold via the PCV valve, which is tied in. In regards to running the combined systems with open headers; you just took a closed system (exhaust evac ) and put a hole in it ( PCV ) making it not very efficient. As far as bung location goes, most suggest an arera right where the primary pipes converge in to the collector and at a 45 degree angle down stream. I actually located mine in the collector extension. At idle with a very scimpy exhaust system, I can pull about 3-4 " of H20 vacuum. Anything above about 1500rpm, the check valves close under pressure and the crankcase starts to build pressure pretty rapidly ( closed system). Mine is a race only application. I only run an exhaust system past the collectors when I am running the engine in my garage at home for some other test purpose. Even at that, I test and once a year replace ) the check valves as a failure there can have bad consequences.