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once again thank you in advance. this site has been great in answering alot of my questions. i have a 78 that the previous owner did a 460 swap. the driver side has a breather type cap on the valve cover. the pass side just has the pcv sitting there, its not hooked up to anything. it has a new holley carb on it.
1) where should i hook the pcv up too? do i need it?
2) can i just replace the pcv with a breahter filter and go on about my day? how will the this affect the engine?
Don't delete the PCV! This is one "emission" item that is actually beneficial to the engine.
It helps keep the engine clean inside. Helps prevent sludge and varnish build up.
The breather on the drivers side v/ cover is okay. The PCV valve should be plugged into the passenger side valve cover and, through a 3/8" line go to a vacuum port on the rear of the Holley carb.
The picture is of a 390 but the carb is a Holley, you get the idea.
man you guys are quick. thanks for the quick replies. i will hook up to the back of my carb and leave the PCV in. Im here in Texas, so after 25 years we only do a safety inspection. emissions dont matter anymore. Once again thanks for your replies
Don't delete the PCV! This is one "emission" item that is actually beneficial to the engine.
It helps keep the engine clean inside. Helps prevent sludge and varnish build up.
The breather on the drivers side v/ cover is okay. The PCV valve should be plugged into the passenger side valve cover and, through a 3/8" line go to a vacuum port on the rear of the Holley carb.
The picture is of a 390 but the carb is a Holley, you get the idea.
To work properly i don't think it matters which valve cover the PCV valve is in as long as the other side is vented, just vent it from your air filter and not just open to the atmosphere and Cali. will be happy.
Thinking of moving to Cali, how do i make sure that i comply?
They don't like tampering with the original system. If you're 1975 or older you exempt.'76 and newer they just want to see everything in place. so just keep it run to the carb plate.
Alright i have another one for yall. I was looking at the set up, the brake booster is hooked up where the pcv should go at the back of the carb. I noticed that my manifold does not have the splitter that MIKE shows in the picture of the 390 (the brass block with the black caps). Mine is just plugged up. Im thinking that the previous owner just plugged it up because he was not going to use the pcv. i want to keep it but want to connect it like MIKE shows. Should i put a splitter back into the manifold to run vacuum for the booster off the manifold? or can i run a splitter off the carb?
Don't hook the "splitter" to the carb. Usually the "splitter" is called a vacuum tree. Hook the brakes to intake manifold vacuum.
If the only line you're going to hook up is the brakes you don't actually need a tree, all you would need is a brass fitting that is 3/8" hose barb X either 1/4, 3/8, or 1/2 NPT male thread, depending on what the hole in your manifold is. You can get these at Lowe's, Home Depot, parts stores or hardware stores.
Just screw it into the intake manifold and hook the hose up.
Alright i have another one for yall. I was looking at the set up, the brake booster is hooked up where the pcv should go at the back of the carb. I noticed that my manifold does not have the splitter that MIKE shows in the picture of the 390 (the brass block with the black caps). Mine is just plugged up. Im thinking that the previous owner just plugged it up because he was not going to use the pcv. i want to keep it but want to connect it like MIKE shows. Should i put a splitter back into the manifold to run vacuum for the booster off the manifold? or can i run a splitter off the carb?
That is a switch used to control vacuum to your EGR valve and possibly other things, do you still have a EGR valve? You should get a vacuum diagram for your truck and reroute as needed.
Thanks stinky, I didn't catch the link.
Stinky is correct, that's a ported vacuum switch. You don't need that. All the vacuum tree is is basically a "mini manifold" so you can hook several different vacuum lines to one source. But, if you're only hooking up one line, you only need the pipe thread to hose barb fitting that I described in the earlier post.
They look like this.
once again thank y'all. i went to home depot and got the plug i needed. i know have the brakes to the manifold and the pcv tot he carb. these are the only two things im running, no other emission things, so tit works out well. thanks