# Do I need to have a PCV valve?



## 9jhiu43 (Jan 6, 2013)

Folks, I have a 66 GTO with the 455 (not stock). I am putting a Edelbrock carb/intake kit on it, which has a front vacuum port labeled for PCV port. The Qjet that I took off was not connected to a PCV. In fact, I don't even have anything that appears to be the PCV going into a valve cover like I have seen on 350's that I've worked on.

Should I have a PCV ? What does it do?


Thanks much


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## fasterfiero (Sep 6, 2011)

YES !!!!! you should always run a pcv system, it does many things, and you will have a bitch of a time getting the carb jetted without one. For starters it removes moister and explosive / corrosive gasses from your crankcase and burns them in the combustion process. You will find no performance advantage of not running a pvc system. The fact is I have seen many run like crap without the pcv working......


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## gjones (Oct 8, 2012)

*pcv*

You can blow out your engine oil seals without one. I've got a (1971) 455 in our '66 Lemans convertible, and have a pcv valve going into the front section of the valley pan to the front port of the carb. You need to have some kind of a system in place to rid the crankcase of fumes and pressure.


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## 9jhiu43 (Jan 6, 2013)

*Thank you!*

Thanks for the quick responses, guys. As a first timer on this forum, I sincerely appreciate it.

Off to Summit....


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## geeteeohguy (Feb 2, 2008)

The Q-jet won't have a PCV provision because the stock Pontiac _intake_ supplies the vacuum. Not the carb. On a Pontiac, the PCV valve goes into the valley pan (pushrod cover) that Chevys don't have. (They run with hot engine oil in contact with their intakes). So, nothing "Chevy" applies here. Run a PCV valve....it increases power by eliminating pressure inside the engine, and it keeps your gaskets and seals oil tight.


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## 9jhiu43 (Jan 6, 2013)

*valley pan*

I hesitate to ask this because I may not like the answer, but if I replaced the stock intake with the Edelbrock, should I have left the valley pan in place? I kind of assumed that it would not be needed with the Edelbrock intake.


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## geeteeohguy (Feb 2, 2008)

You can not run the engine with no valley pan. It leaves the engine open, and unprotected...even worse than having no valve covers. But, you'd have found that out when you tried to fire it up and saw oil spray everywhere!!


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## 9jhiu43 (Jan 6, 2013)

Please forgive my ignorance, but where would oil spray from if the intake manifold is in place with the correct seals? 

I am clearly missing something here. 

Thanks


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## 05GTO (Oct 6, 2004)

9jhiu43 said:


> Please forgive my ignorance, but where would oil spray from if the intake manifold is in place with the correct seals?
> 
> I am clearly missing something here.
> 
> Thanks


Can you post pictures of the engine? Could it be a chevy 454?


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## 9jhiu43 (Jan 6, 2013)

It's not a Chevy. The block is an Olds 396021F. The intake is Edelbrock 2151.

Attached are a couple of pics of when I had it opened up.


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## geeteeohguy (Feb 2, 2008)

An Olds is an entirely different animal than a Pontiac. No valley pan. You're ok....just use a PCV valve!


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## 9jhiu43 (Jan 6, 2013)

Glad to hear it! I was getting nervous about having to pull the intake back off and starting over. 

Thanks for the guidance....


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## Tropical Goat (Jan 30, 2011)

In the early 80's, My brother had a 66' with a stock 70' Olds 455 in it.
With torque around 500 lbs., it was a real tire shredder!...we had a ball with it!
Now I've got a 66' with a "tweaked" 67' 400 pontiac in it, and I'll tell ya, I don't miss the
Olds at all! But still...enjoy what you got!...we sure did!


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