1966 427 425 correct thermostat housing

[Joe R.]

Re: 1966 427 425 correct thermostat housing

Joe,

What dimple are you referring to?

The one in that ebay sale had one on the long bolt side and two on the short bolt side. If you look carefully in those dimples, you will see ejection pin bosses.

Another thing to study is the cavity number. The parts that are considered 68 or later - with the number on the neck, what cavity numbers are you seeing?

Even in 1966 for usage on Chevelle, Corvette and others one cavity would not have been able to keep up. If there was a different supplier - chances are that the Tonawanda plant got theirs from a different location versus Flint.


I saw an odd feature - a die cast ejection pin boss partially up the neck - in what appeared to be a repro, don't know where that photo is right now, but I have never seen that on old parts from the 70's or from original cars.

I hope you make progress on the 66 JG - keep us in the loop!

Ron,

If you go back to post #11 and click on the link, it will take you an eBay picture. There's one depression near the long bolt hole, two depressions next to the short bolt.

Joe

[Jim C.]

Re: 1966 427 425 correct thermostat housing

Joe,

I don't have photos of the first one but VERY clearly remember it, and can tell you why, if you're interested. My current car has the 3877660 thermostat housing too. It's currently installed on the car. The fuel line runs directly in front of the thermostat housing across the top of the flange, partially obscuring the part number. I'll try for a photo, but I'm not sure I'll get the entire number.

Jim C.

[Joe L.]

Re: 1966 427 425 correct thermostat housing

Jack -

I don't think either the Saginaw or Tonawanda foundries had aluminum die-casting capability in the 60's; I believe the 660 housing was purchased.

John------



Yes, I think the only GM foundry that ever had aluminum die casting capability was/is Bedford, IN. I doubt that they ever cast these thermostat housings but I suppose it's possible they did some of them. Some of these '660' housings I have seen clearly have some outside manufacturer's ID symbol on them.

This brings up an interesting issue that I've mentioned many times before. Just about every GM parts drawing that I've seen specifies that a manufacturer's ID mark MUST appear on the piece and "deletion requires approval". However, very few GM parts from the era have a manufacturer's ID ANYWHERE to be found on them. Even if deletion was requested by the manufacturer (and I can't imagine why they would make such a request), I don't understand why anyone at GM would have approved such a request.

[Ronald L.]

Re: 1966 427 425 correct thermostat housing

Joe,
Most all parts form the era do have those suppliers ID's fasteners, brackets, trim parts - like close out panels and carpet - on the underside.

Even the internal stuff got lots of identification - what parts are you thinking of that don't have source identity?

[Joe L.]

Re: 1966 427 425 correct thermostat housing

Joe,
Most all parts form the era do have those suppliers ID's fasteners, brackets, trim parts - like close out panels and carpet - on the underside.

Even the internal stuff got lots of identification - what parts are you thinking of that don't have source identity?

Ronald------


There are huge numbers that don't. Just a few:

most harmonic balancers do not

most pullies do not

most brackets that I've seen do not

[Joe R.]

Re: 1966 427 425 correct thermostat housing

Joe,

I don't have photos of the first one but VERY clearly remember it, and can tell you why, if you're interested. My current car has the 3877660 thermostat housing too. It's currently installed on the car. The fuel line runs directly in front of the thermostat housing across the top of the flange, partially obscuring the part number. I'll try for a photo, but I'm not sure I'll get the entire number.

Jim C.

Jim,

Sure, tell me why you remember it clearly. That's the original water neck on your current car, right? Any photos would be appreciated!

Joe

[Jim C.]

Re: 1966 427 425 correct thermostat housing

Joe,

I'll send you a PM in order to avoid boring the rest of the participants on the board.

Jim C.

[Ronald L.]

Re: 1966 427 425 correct thermostat housing

Its about time to reinvigorate this thread, after a few years, corroborating what Pete mentioned a few years ago, looking at other Chevrolet's...you will find with probability, that the supplier to Tonawanda was different than the supplier to Flint for these 660 goose necks. Not only that, but there were more 327 produced for all Chevy that 396-427 and via a separate thread it's been confirmed that all 396 427 went down ONE asy line, so if it was a Corvette, Impala, Chevelle, they would not get a different goose neck.

If you go to the Chevelle's and others, and again cars and intakes that are un molested and some of the early 396's that no one ever would have changed the goose neck...
Numbers on the flange - Flint
Numbers for 66 67 396-427 - on the neck and there will be 2 very special characteristics that I have seen on real un molested cars, Corvette and other BB Chevy.

[Matt L.]

Re: 1966 427 425 correct thermostat housing

hello all. i ran across this thread tonight and thought i would share my thermosat housing from my 66 425 car. it is original to the car. engine build early april. hope this helps.
take care,
Matt66 vette exhaust clamps 758.jpg

[Ronald L.]

Re: 1966 427 425 correct thermostat housing

Matt, Always good to see pics from your car and that is exactly what I was describing a few years ago. So my sample size is two 66 BB, both numbers on the neck.

First car was purchased in 1978 long before NCRS knew they'd call a C2 a C2, and unmolested. There are two subtle details to this neck that make it stand out.

And also this same neck is seen on early un molested low mileage 67BB.