Crankcase Evac Setup

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SloCar1422

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Looking to see where in the header you guys have placed the bung for a crankcase evac system. I am installing a set of Doug's d453 headers into my small block bracket car Duster with the stock firewall and hoping to see the best placement to avoid clearance issues. Thanks!
 
As far back on the collector as you can get.

We have issues with the one way in them sticking and pressuring the crank case.

I'd run twin breathers before going header evac.

Our dyno headers and run stand headers have em but they sure dont last long....

If your not checking them each time you fire up your risking forcing pressure INTO your crankcase and blowing out the main seals....
 
Cope said:
As far back on the collector as you can get.

We have issues with the one way in them sticking and pressuring the crank case.

I'd run twin breathers before going header evac.

Our dyno headers and run stand headers have em but they sure dont last long....

If your not checking them each time you fire up your risking forcing pressure INTO your crankcase and blowing out the main seals....
Click to expand...
did not know that, thanks for the heads-up.
 
I realy enjoy the look but my "race car" runs on the street and I do not want to pull the fitting off, fire the engine, make sure it's not blowing out the fitting and drive.
So if it's not a full, all out race only car I would not wanna risk it.

Those dam fitting can stick at any time and then you're looking at a pan removal.
 
I've always run my evac systems with closed valve covers,that is to say nothing but the evac breathers,no other breathers.
Am I correct in my thinking?
 
SBeeMan said:
I've always run my evac systems with closed valve covers,that is to say nothing but the evac breathers,no other breathers.
Am I correct in my thinking?
Click to expand...

That is how we have always done it. I am wondering where in the collector to locate the hose nipple so that it won't hit the torsion bars, firewall, transmission etc.

I think Cope makes a valid point above. On an open headered drag car how much backpressure would feed back into the motor if the check valve failed?
 
Do you need a check valve with open headers. Same thing happened to my friends car. Both were stuck shut. I always put mine in the collector extentions.
 
I always put mine in the extentions as close to the flange as I can.
 
Pull the fitting and place your hand over it.



If its blowing out air, your check valve is bad and its pushing air into the crankcase.
 
If you going from idle to 7,000 plus.

Ok it can work.

If not run a vacuum pump.

Or just let it blow out the breathers.
 
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