[60sstuff]

It seems the judging of the Big Boy cars at the Big shows is pretty intense these days as it should be to separate the contenders from the pretenders.

I wonder how many judges (and owners) are aware of the "period correct" PCV Valve on a 65/66 GTO? I'm sure other years apply but I only have these two as reference.

The physical construction of the 65/66 dated examples below is a "heavy thick cast" style opposed to the commonly seen and used "light stamped steel" version.

Both use the same AC identification (CV679C #6421972).

Because of the location on the car of this valve it will be difficult to determine which style PCV valve is being used unless you detect the additional upper shoulder on the new style.

Ok, run out to the garage and check.

[60sstuff]

The all important GASKET!

Have to have this with that early valve to really score the points!

Last pic shows this dark gray gasket on a 26,000 mile Original 65, courtesy of Roger!

[dld]

what also looks to be a molded PVC hose?

I'm thinkin they accept repro's. don't think there is extra credit for o.e or nos. not saying thats the way it should be.

[geeteeohguy]

I pulled a cast PCV off both of mine 30 years ago...still may have the one off the '67 somewhere.....I remembered at the time how odd it seemed...way overbuilt for the job at hand! As usual, more arcane and unknown 'stuff' from '60sstuff'!!

[Dick Boneske]

The judges didn't look to see what kind of PCV I have on my '64. I didn't see a points award or deduction for the PCV, only that the engine had one in the right location. I don't think you can see the gasket without removing the PCV from the valley cover.

[bill ryder]

So what is the thought on this one on ebay? NO C "Bill"!

http://www.ebay.com/itm/NOS-AC-PCV-V...4c7e8a&vxp=mtr

[dld]

think some goof bought it

[Option 382]

Each week 60sstuff will bring up a new subject to spend money on.

[dld]

On the thought of what Judges know. Admittedly I I'm of little knowledge of protocol or much else about GTOAA judging. But my first experience I thought they were pretty thorough. I had a point taken also for ground straps. comment was (upside down). see pic. cable end at coil bracket.

So. even though there is not a specific PCV instruction on judging sheet . there is a misc. column for whatever. where you could lose up to 10 points at judges discretion. would not surprise me for them not to pick up on a PCV valve.
I noticed one judge using a digital camera to inspect items hard to view.

[dld]

Originally Posted by 60sstuff

The all important GASKET!

Have to have this with that early valve to really score the points!

Last pic shows this dark gray gasket on a 26,000 mile Original 65, courtesy of Roger!

The last pic 3rd. is that of a 67 car. noted the molded hose. was that command to a 64-65 car?

thanks for post

[60sstuff]

Originally Posted by dld

The last pic 3rd. is that of a 67 car. noted the molded hose. was that command to a 64-65 car?

thanks for post

Not sure what you are asking but the 3rd pic in my post #2 is as I said in the text - 26,000 mile Original 65 GTO. Not a 67.

The hose going from the three way plastic connector down and around to the PCV Valve was not a molded hose. It was just hose with the G A S printed on it which was also used at other locations on the 64,65,66 GTO's.

PS - the point you lost because of the coil ground strap end was (upside down) is BS!
How many times do you think the assembly line guys installed it that way because it didn't matter anyway.....it's being grounded as it was designed to!

[60sstuff]

Originally Posted by bill ryder

So what is the thought on this one on ebay? NO C "Bill"!

http://www.ebay.com/itm/NOS-AC-PCV-V...4c7e8a&vxp=mtr

I saw this valve on ebay that did not have the "C" and listed a 64 date on the box but the parts book says CV679C is correct for 63-66 T8 as shown below with red line. Possibly be a revised part number that added the "C"?

Plus the seller hit it with the dreaded wire wheel. Yikes!

[dld]

I agree on ground .

but on your pic it looks like hose is molded . no problem just askin.

I may be naive but i think every one knows the modern day PCV or repro valves are only similar in appearance and only effective.

reading sellers comments .the valve he lists is older than your examples. this reminds me of the oil filter thing a wile ago that you were involved with. thats were I learned about checking the box date. thanks for that.

[60sstuff]

Originally Posted by dld

I agree on ground .

but on your pic it looks like hose is molded . no problem just askin.

I may be naive but i think every one knows the modern day PCV or repro valves are only similar in appearance and only effective.

reading sellers comments .the valve he lists is older than your examples. this reminds me of the oil filter thing a wile ago that you were involved with. thats were I learned about checking the box date. thanks for that.

You are very welcome! I love this OEM detail stuff!

BTW, your Red 65 is Awesome (Very Nice Work) and sounds like it just needs a few little items corrected to dial it in.

[dld]

here's what i'm styling with. most likely like 99% of the cars. but you pic looks like the hose has a 90. probably just me not looking at it incorrect.

[dld]

Originally Posted by 60sstuff

You are very welcome! I love this OEM detail stuff!

BTW, your Red 65 is Awesome (Very Nice Work) and sounds like it just needs a few little items corrected to dial it in.

Me to . YOU GUYS JUST DON'T KNOW how much you have helped me with my first build

[60sstuff]

Originally Posted by dld

here's what i'm styling with. most likely like 99% of the cars. but you pic looks like the hose has a 90. probably just me not looking at it incorrect.

Well Roger's 65 is Very Special so maybe it has a "one of a kind" molded hose going to the PCV valve. NOT!

I think it's just the angle of the photo that makes the hose look like it has a formed bend in it.

Your 65 must be early because it has the bare metal brackets on the firewall for the engine wire harness. Later 65's were rubber dipped.

[bill ryder]

Stumbled across this one the other day!! What we learn on this forum is amazing!!!!! "Bill"!

[dld]

Your on spot with that . Bill . I built my hole car off this forum and my buds Jon Haslip and Mark Mento.

got the valve you posted. not as bad as could be given the wire wheel clean up. no real fix on the surface rust . I treated it with metal prep. its ok but!

do you think there was a plating oe

[John V.]

For '64, the AMA specs show that the GTO got PCV Valve CV-273.

Same as for the 326.

GM p/n 5646286 was assigned to the CV-273 (not noted in the AMA specs).

When GM discontinued this p/n it was superseded by p/n 6421972 which matches to CV-679C although I also found a Nov '67 Chevy MPC that listed some applications for the 6421972 but identified it as a CV-608, I have no idea if this was an error or if there is some other explanation. I believe the CV-679C is different from the CV-679, possibly a revision that enabled the CV-679C to service both open and closed systems but this is strictly a guess.

The '64 AMA specs do not indicate the p/n for the Calif Closed Circuit PCV Valve, but the '64 Tempest Inspector's Guide notes that the standard PCV Valve is to be returned to stock and replaced by p/n 6419534 (not very legible on my copy but I believe this is the p/n indicated).

I have not been able to find an AC valve no. to match to this p/n but the p/n has been confirmed as a PCV valve p/n.

There is no way for me to know if the '64 PCV valve was revised during the production run but it my belief that the '66 MPC listing is not accurate for the PCV Valves used at least for some part of the '64 production run.

It would be useful to check a '64 MPC, both original issue and any subsequent revision, but I don't have a copy of that MPC.

For my part, I believe the CV-273 is correct for the regular '64 GTO PCV valve.

I'd be interested in learning what PCV valves are listed in the '65 AMA specs. If they had not yet been changed from '64, perhaps it will indicate the PCV valve for the closed system.