Old School Valve Covers

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hoosierdaddy

hoosierdaddy

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I need someone to educate me , I have a set of old Edelbrock valve covers and I'm trying to figure out how to hook up a PCV valve and the only thing that works in my mind is a Ford style breather cap . Also at the cap openings there is a plate/baffle inside which would make adding oil a pain in the butt , should I remove these ?

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Do some searching, there are a couple of threads on this
 
Interesting.
The cap is just a typical 1/4 turn valve cover cap, easy to find.
Guess one cap was a vent and other side was for pcv.
My covers came without anything, and i found the proper parts on amazon. One breather and grommet,and pcv grommet for other cover.
 
If i had these covers, i would have my machinist buddy mill for a pcv grommet and vent. Then just out the caps on the existing holes.
 
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I was almost in the same boat, but my covers i assume are a little newer, so the holes were just round. I think i flipped them side to side now so pcv is at the back. If my power wagon wasnt away in storage i would check those covers, i believe they are similar.
 
hoosierdaddy said:
Oh by the way there is no place to drill for a PCV grommet
Click to expand...

Sure there is, you could use a hole saw (in a drill) of appropriate size and put a hole in further back on that cover, then using a die grinder work the ribs down around the hole to accept a grommet and install a PCV. The one minor issue would be figuring out how to put a baffle under the hole to keep splashing oil away from the valve.

Take your time and move carefully and it would look fine.
 
Couldn't you just put the PCV valve in the line? Instead of in the valve cover itself? It is just a one-way valve correct?
 
j par said:
Couldn't you just put the PCV valve in the line? Instead of in the valve cover itself? It is just a one-way valve correct?
Click to expand...


That exactly what I did on my 340, I had the gold Moroso VC think aluminum and I had 1 breather going to the air cleaner and the other breather that had a 5/8 hose I shoved the fat part of the PCV into and the small end to ther carb base and it worked great.
 
BTW I love the old VC they don't make them with the fat ribs anymore.
 
Just use the ford style breather with the pvc built into the cap and be done with it. It will work just fine. I wouldn't go drilling into those beautiful valve covers to add a pvc valve.
 
BTW, whatever PCV valve you use, search around to see what vacuum level the valve opens from the low flow idle setting to the high flow setting. If you have a cam that lowers the vacuum level at idle, a lot of stock PCV's will be at the wide open setting at normal idle, which they should not be, and that will dump a lot of air into the intake. That makes carb tuning more difficult in idle to low cruise transition, since when at low level cruise, the vacuum level will go up and the valve will close down, putting less air into the intake. That 'backwards' air flow change into the intake is not what the carb is set up work with.

For example, the stock Mopar PCV opens up to cruise flow at something like 14-15 in vacuum.... using one with a cam that drops the idle vacuum to a lower level can result in these issues.
 
That reminds me the breather I used was aftermarket and the tube came out at 45* so I found a molded hose that had a bend in it and cut it so my PCV valve was straight up not at a angle.
 
nm9stheham said:
BTW, whatever PCV valve you use, search around to see what vacuum level the valve opens from the low flow idle setting to the high flow setting. If you have a cam that lowers the vacuum level at idle, a lot of stock PCV's will be at the wide open setting at normal idle, which they should not be, and that will dump a lot of air into the intake. That makes carb tuning more difficult in idle to low cruise transition, since when at low level cruise, the vacuum level will go up and the valve will close down, putting less air into the intake. That 'backwards' air flow change into the intake is not what the carb is set up work with.

For example, the stock Mopar PCV opens up to cruise flow at something like 14-15 in vacuum.... using one with a cam that drops the idle vacuum to a lower level can result in these issues.
Click to expand...

This motor has a computer cam in it which should be fairly high vacuum .
 
PCV can just be a hose routed to the top of the carb or air cleaner. dont try and run it to the base like a power brake spud. Its not EGR.
 
pishta said:
PCV can just be a hose routed to the top of the carb or air cleaner. dont try and run it to the base like a power brake spud. Its not EGR.
Click to expand...

It is suppose to go to the base plate of the carb, PB booster goes to the manifold plenum or runner.
 
If your cam generates stock vacuum levels, run it via manifold vacuum. If your motor is built with a high overlap cam or non standard vacuum levels at idle, your stock pcv valve will play havoc on your idle. Im not convinced you need to run pcv via manifold vacuum. Ported vacuum above butterfly makes more sense to me.
 
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