PCV valve - Pontiac GTO Forum
User Tag List

 
LinkBack Thread Tools Display Modes
post #1 of 5 (permalink) Old 11-20-2012, 04:56 PM Thread Starter
 
Join Date: Nov 2011
Posts: 7
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
PCV valve

I need high performance PCV valve. 1970 455 flat tops, #96 heads, Bullet (hydraulic roller) cam...230/238 530/530 on a 112. Suppose to have 4 degrees advance already in it, so its installed straight up. 0 lash and a quarter turn on 1.62 roller rockers.
Have about 9.5-10 inches of vacuum at 750-800 idle rpm. If I unplug ( and block off the carb and pcv tube) the PCV, I get 12.5 inches of vacuum.

I figure the current PCV is rated wrong for this application, therefore wondering if anyone has a P/N for a lower vacuum rated PCV.

Thanks!
Fairlane514 is offline  
Sponsored Links
Advertisement
 
post #2 of 5 (permalink) Old 11-21-2012, 01:10 PM
Super Moderator
 
BearGFR's Avatar
 
Join Date: Aug 2008
Location: Springtown, TX
Posts: 4,948
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Garage
Well... strip my gears and call me shiftless... I think I have a similar issue and it didn't register with me until I read your post. I don't have an answer but I'm sure interested in hearing if someone does.

Bear

BearGFR
Garland, TEXAS
BearGFR is offline  
post #3 of 5 (permalink) Old 11-22-2012, 09:09 AM Thread Starter
 
Join Date: Nov 2011
Posts: 7
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I found one for a 1970 Chevelle 454 LS6.

Here's an interesting article.

Positive Crankcase Ventilation (PCV)
Fairlane514 is offline  
post #4 of 5 (permalink) Old 11-22-2012, 10:36 AM
 
the65gto's Avatar
 
Join Date: Oct 2008
Location: Florida
Posts: 260
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I think I might do some "shade tree" testing by inserting an adjustable valve (plumbing dept at L or HD) in line with the PCV hose. Adjustment somewhere between fully open/closed and note the results. ?? Assume that the needed results will be less of a vacuum draw from the engine but enough for PCV action ??
the65gto is online now  
post #5 of 5 (permalink) Old 11-22-2012, 07:00 PM Thread Starter
 
Join Date: Nov 2011
Posts: 7
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I feel like I should have between 12-14 inches of vacuum at 800 rpm, but I only have 9.5-10. My valve lash is 1/4 past 0, but its a consideration to go to 1/8 or even 0 lash to gain some more vacuum. Normally this wouldn't be necessary on this camshaft specs.

Trying to think outside of the box, I am going to try a different PCV and see if I gain some vacuum. Its possible the one I have now is rated for a closer to stock cam with 15-17 inches of vacuum.

I am always trying to learn more and pass information on, if it will help someone else.
Fairlane514 is offline  
Sponsored Links
Advertisement
 
Reply

  Pontiac GTO Forum > The 1964-1974 Pontiac Tempest, Lemans & GTO > 1964-1974 Tempest, LeMans & GTO Technical and Electrical Wiring
Gear in this thread - Powered by O'Reilly Auto Parts

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Pontiac GTO Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 2 (0 members and 2 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
metering valve Topkat 1964-1974 Tempest, Lemans & GTO General Discussion 1 04-18-2011 12:20 AM
'70-72 POA Valve krafty 1964-1974 GTO parts for sale (Price & Pictures Required) 1 04-13-2011 10:13 AM
valve tapping xcmac26 1964-1974 Tempest, LeMans & GTO Technical and Electrical Wiring 65 05-04-2010 07:05 PM
Little Air Valve beside Gas Cap goatgirl70 1964-1974 Tempest, LeMans & GTO Technical and Electrical Wiring 6 08-18-2009 08:40 AM
A/C Valve color GearheadPG 1964-1974 Tempest, Lemans & GTO General Discussion 0 01-30-2009 03:03 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome