Has anyone tried using a thread in style valve from an Olds on their intake? I'm thinking of using this one on the rear port of a B4B intake to keep everything nice and hidden but still functional. Here's the description: 4-SEASONS NON-BYPASS VACUUM HEATER VALVE -- 5/8 in. 3/4 in. NPT x 5/16 in. NF thread fitting size; Vacuum closes; A high quality, direct fit OE replacement non-bypass vacuum heater valve; Can be used on vehicles with or without screw-in thermal sensor Anyone have any ideas about it?
Get an idea on function before you buy it. My '71 Skylark uses one similar & opens on applied vacuum. Large body car same year or close uses one that opens on vacuum loss. Possibly earlier A-body car I'm thinking of but there are differences. Each control panel operated differently, make sure you can control it.
I have yet to find one of these in the 1/2" size that the intake uses. Every one is 5/8" npt. I can't even find an adapter that'll let me use it in the 1/2" hole. I guess to use this I'd need to drill and retap the intake
I used an Olds valve on an edelbrock and it worked perfectly. Just try a NAPA and get the right thread size. 70 Olds used different thread size than 71-72. One of them does fit however as I am proof. You can also get an adapter from a plumbing supply house. I have an NOS olds valve for an Olds is the correct as I used before but it is discontinued part I may hang onto to get top $ from an Olds guy. .....I also checked my Olds valve and it does fit the stock intake thread which should be the same size. The GM part was 231782 AC Delco from samebox # was #15-5107. Maybe NAPA can cross reference?
Just to clarify The one I have is the same size as the stock Buick brass fitting that goes at an angle into the front of the stock Buick intake. The Edlebrock performer was the same size. Not sure on the B4B.
Looking it up now. Looks like the Olds motors from 68-70 used a smaller fitting. Your part numbers come up as obsolete, but they list as the original valve for the 68-70 442's which means you may be in for some big bucks on ebay.
4-seasons part number 74601 Perfect for you early A-body guys. Not so much for me. I need normally open and this is normally closed. For '73 the vacuum to the valve is only applied when the controls are set to A/C. That means the valve needs to be normally open and then close when the vacuum is applied during A/C usage. :af:
I think I found one that'll work. It's a 1/2" npt fitting with a 5/8" hose barb. Vacuum closes the valve. It's even for GM's. Can't let out the part number until I get it ordered though. No use figuring it all out and having someone else buy up the last one :laugh: Plus it's only $18 at autozone and I have $20 in free suff available to me :grin:
