'66 Thermostat Housing

[Rob M.]

All,
According the JG, the thermostat housing for a '66/300 horse motor should be GM#3877660. They state that the part number was "typically" cast onto the mounting flange and has a recessed web area on each side of the two attaching bolts. So, here is a photo of the one pulled from my engine some time ago. I would like to know from those who may know if this is likely original/correct or if it is likely a later service replacement as the configuration differs from what the JG shows. Thank you in advance for your insight.
Cheers

[Keith B.]

Re: '66 Thermostat Housing

typical of 68 and up

[Rob M.]

Re: '66 Thermostat Housing

Thank you for the response.

[Rob M.]

Re: '66 Thermostat Housing

In looking at the part offered by LIC, it is very similar to mine as far as the part number location. But, it also has the recessed area like the one pictured in the JG. So, is it wrong too?

[Keith B.]

Re: '66 Thermostat Housing

There were several design changes over the years and for diffreant applactions on Corvettes and Passenger cars and trucks. The one you want will have the numbers on the flange and a eyelet for a spring on the base. They are everywhere for sale on the net.

[Joe R.]

Re: '66 Thermostat Housing

Here is another 660 that came from a 66 also. The word TYPICAL is used in the judging manual to allow a judge with basically no knowledge of what he is doing to take points away because of his ignorance.

JR

[Keith B.]

Re: '66 Thermostat Housing

found this in a search on here.

https://www.ncrs.org/ok/May_2016_Sidepipe.pdf

[Rob M.]

Re: '66 Thermostat Housing

Thanks Keith for the article. It was interesting to see so many variants of the same housing. Mine is very much like Joe's other than the mine has the part number flipped and also has the 1C and triangle boss on the neck. The spring hole is also there. I would love to see a bowtie car/one owner around my build date to see what's there. I just know why a prior owner would change that?