326 water pump

[mcditalia]

I am replacing my water pump with a rebuilt #326. Since my car was built mid nov 65, I am assuming that a correct version could be undated since dating began approximatley in Nov 65 according to TIM. I have asked this question before regarding the GM1,2,3...etc. castings and their significance. One explanation I got was that they are foundry pattern numbers used to identify molds used for the part and another was the number of times a batch was run of the part in question. Any opinions on this matter?

Just for kicks, how do the "GM" numbers come into play for judging if at all?

Lastly, would anyone have any objections to an undated GM3 #326 pump used on my car and why?

 

[c5vetter]

mold identifiers and are not judged by NCRS

 

[JohnZ]

I have asked this question before regarding the GM1,2,3...etc. castings and their significance. One explanation I got was that they are foundry pattern numbers used to identify molds used for the part and another was the number of times a batch was run of the part in question. Any opinions on this matter?

Not an opinion - a FACT: They're foundry pattern numbers, and have no importance in judging.

An undated 326 pump wouldn't be unusual for your car's build date.