School me on 340 exhaust manifolds

krazykuda said
No, the model year starts in June of the year before. They started 1970 model year production in June/July of 69. It ended in May/June of 70.

Production and SPD's for model years routinely began on or about Aug 1

Cars for the current year were built into July of that year

Here is a VERY early 1970 built car as an example
http://www.carmemories.com/cgi-bin/viewexperience.cgi?experience_id=181