Thermostat Housing for 66 427

[Christopher A.]

I just found out last week that i have the incorrect thermostat housing for my 66 427/390hp California car with A.I.R., air injection reactor. This was one of the few parts that were missing when i purchased the car almost 3 years ago. I simply thought that this engine used the same as the regular 427 with an aluminum spacer under it, but i was wrong.

The correct thermostat housing is a cast iron unit with part # 3827369. The judging manual does not state if there is a date or not, so i assume that the housing is therefore not dated. However, the only ones i can find on ebay, etc. are dated 1963 or 1964.
Can someone please confirm if the thermostat housing for my particular car is not supposed to be dated for 1966? If anyone has one for sale, please let me know.


Thanks

[David L.]

Re: Thermostat Housing for 66 427

My 1966 Chevrolet Parts Catalog (Oct. 1965) does not list a thermostat housing for the 1966 Corvette w/427. However, my 1967 Chevrolet Parts catalog (April 1967) lists GM # 3827369 in Gr. 1.153 for 1966 Corvette w/A.I.R. (427) and describes it as "cast iron (cast 3827369)".

I have never seen a date code on any thermostat housing made in the 1960's. Years ago I had a "3827369" cast iron thermostat housing with a "B1" casting (mold #, I believe).

Dave

[Christopher A.]

Re: Thermostat Housing for 66 427

Thanks for the info!
I did a quick search on ebay last night and about 6 of the housings came up, most of which were dated for 63 or 64. I will keep my eyes out for a non dated unit that only shows the part number.

[David L.]

Re: Thermostat Housing for 66 427

Thanks for the info!
I did a quick search on ebay last night and about 6 of the housings came up, most of which were dated for 63 or 64. I will keep my eyes out for a non dated unit that only shows the part number.

The "B1", "B3", and "B4" casting are a mold numbers, not a date code. The 3827369 thermostat housing was first used on the 1963 Corvette (exc. F.I.) and did NOT exist in 1961. It would be quite strange if these housing were only made in February. The 3827369 housings made in later years did not even have a "3827369" casting number.

Dave

[Gary J.]

Re: Thermostat Housing for 66 427

A picture of the housing is on page 110 of the new 1966 judging manual. The number is across the top.

[Christopher A.]

Re: Thermostat Housing for 66 427

Thanks for the info!
I was wondering why all of them seemed to be dated the same.

[Ronald L.]

Re: Thermostat Housing for 66 427

If the 63 64 part is the same and are dated, why would the 66 not be dated?

[David L.]

Re: Thermostat Housing for 66 427

Has anyone ever seen a housing with something other then "B1", "B2", "B3", or "B4"?

Is seems that only the letter "B" was used. If this was a date code that would mean the housings were only made in February. I find that hard to believe. The code is a MOLDING NUMBER.

Dave

[John H.]

Re: Thermostat Housing for 66 427

Is seems that only the letter "B" was used. If this was a date code that would mean the housings were only made in February. I find that hard to believe. The code is a MOLDING NUMBER.

Dave

Dave -

That's correct - in foundry parlance, it's a "pattern number"; the pattern (from which the cope and drag of the sand mold were made) was made of iron or stainless steel, and when there were multiple patterns for higher-volume castings, each pattern was numbered for foundry process traceability (like the GM1, GM2, GM3, etc. you see on blocks and heads).