Hello:

Is it most certain that zero July model year 1966 3855962 Engine blocks were offered by Chevrolet and that infact the 1967 model year blocks part numbered 3902406 official began initial production begining in July of 1966 thus were offered in July 1966 model year cars?

If so, would the same hold true for other items such as intake manifolds and heads etc?

I have a 4th week of July build date as stated by my cowl tag 1966 Chevelle SS and wondering if I need to forgo early to mid "F" June parts and seek "G" July parts of which may infact be part numbered for model year 1967.....

I spoke to a man who has a "G" July 1966 3904351 427 Corvette Block of which he claims if for a very late model year 1966 Corvette in lieu of early 1967 Corvette of which the part number of 3904351 indicates.

Please input and thank you again.