PCV Valve, to connect or not?

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73Dart340Sport

73Dart340Sport

73dart340
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I have a question for the "most knowledgable folks" on-line at "For A-Bodies Only!

I have a BG 650 Claw on my 73 Dart 340. The car did well on it's
annual compression check, and pulls 7.5" HG with the curb idle adjusted inward to 1.5 turns and then richened to 1 5/8s (or somewhere in that neighborhood) with cam duration of 236/244 at .05".

The car, being a 73 model, is equipped with a Filter on the left valve cover,
and a PCV valve on the right valve cover. Right now I do not have the PCV valve connected to either the air filter assy, or the vacuum port on the bottom of the carb. I understand that the PCV valve scavenges blow by and then consumes it through the combustion chamber.

Question 1. By running the car with the PCV disconnected at high RPMs, am I causing a pressure build up in the Crankcase that can affect my performance.....or cause a discharge of smoke?

Question 2. My old air cleaner had/has a port for the PCV hose. (right now it is sealed off) I note that my Claw Carb has a vacuum port at the base. If I decide that it is in my best interest to hook up my PCV, , and use my present Air Cleaner port (old edelbrock) then I'm pulling the scavenged air into the air cleaner, then the horn and mixing it with fuel, which would give me an artificially lean mixture in the horn. If I hook the PCV hose to the base-plate on my Claw, then I'm pulling the scavenged blow-by into the plenum, which is below my fresh charge of Air/Fuel. Which is the best route for hook-up? Also, I use Rush Filters. Are there any advances in the actual air cleaner housing that can create additional efficiencies?

As always, thanx for any input!
 
The tube on the aircleaner gets hooked up to a breather on one valve cover.The pcv valve gets hooked up to the large port at the carb base or into the back of the intake.And yes you really need them both
 
73Dart340Sport said:
I have a question for the "most knowledgable folks" on-line at "For A-Bodies Only!

I have a BG 650 Claw on my 73 Dart 340. The car did well on it's
annual compression check, and pulls 7.5" HG with the curb idle adjusted inward to 1.5 turns and then richened to 1 5/8s (or somewhere in that neighborhood) with cam duration of 236/244 at .05".

The car, being a 73 model, is equipped with a Filter on the left valve cover,
and a PCV valve on the right valve cover. Right now I do not have the PCV valve connected to either the air filter assy, or the vacuum port on the bottom of the carb. I understand that the PCV valve scavenges blow by and then consumes it through the combustion chamber.

Question 1. By running the car with the PCV disconnected at high RPMs, am I causing a pressure build up in the Crankcase that can affect my performance.....or cause a discharge of smoke?

Question 2. My old air cleaner had/has a port for the PCV hose. (right now it is sealed off) I note that my Claw Carb has a vacuum port at the base. If I decide that it is in my best interest to hook up my PCV, , and use my present Air Cleaner port (old edelbrock) then I'm pulling the scavenged air into the air cleaner, then the horn and mixing it with fuel, which would give me an artificially lean mixture in the horn. If I hook the PCV hose to the base-plate on my Claw, then I'm pulling the scavenged blow-by into the plenum, which is below my fresh charge of Air/Fuel. Which is the best route for hook-up? Also, I use Rush Filters. Are there any advances in the actual air cleaner housing that can create additional efficiencies?

As always, thanx for any input!
Click to expand...

By not running a pcv you are building up pressure in the crankcase,which can lead to oil leaks and blowbye..
 
Thanks!

However, the question now is should I connect the PCV valve to the air cleaner assembly, or the base of the carb?
 
Thanks. I should have read the earlier post more carefully.

One thing I'm curious about though. Why are so many people adamant about not connecting up the PCV. I'm becoming a believer, but at the last car show I went to, I noticed a large number of cars with the chrome filters on both valve covers, and no PCV hookups.

As always, thanks for the good feedback!
 
It can contaminate the incoming airc charge. But thats nothing I would worry about on a street car Im running a PVC valve and have all the lines hooked up to my air cleaner, carb and vent line from the breather on my valve cover.

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All street engines should run PCV
otherwise you risk contaminating your oil with fuel,water,etc.
the only reason i can think of you might NOT be running a PCV is maybe a race engine that is torn down frequently and the oil changed every race
 
First off, those are a pair of cute future Mopar drivers you have Adam R.

Excellent information. Last year my brother was getting his 360 Dart dyno'ed on a chassis dyno. Every time the engine hit 5000 RPM the shop was filled with smoke. The owner of the dyno had suggested hooking up the PCV, but that did not happen. No problems could be found, and the engine subsequently passed a comp check and leak down with flying colors. No smoke while the engine was unloaded at 5000 RPM. I have since wondered if not having the PCV connected was the causal factor for the smoke!

Thanks to all for the input!
 
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