I have been trying to do research on my 69 Mach 1 which has a 390. There is a million articles out there with a lot of contradicting information. I am looking for someone who has a wealth of knowledge on the motor or who can point me in the right direction to get these below questions answered.
1. In 1969 did the 390 Block have a casting number and if so where was it located? Where they all in the same place? I am having issues finding one
2. I read that all 390's were assembled at the Dearborn plant. Any info to confirm this?
3. My car was build on 3-28-69 The block date on my car is 9 B 28 so Feb 28 69 which appears correct to the car. Any info to say that its not close enough to be original?
4. My heads have two different date codes Driver side is 9 B 19 and Pass side is 9 B 20 Should they be the same date ? I read that engine parts that are close in date were used and not always the same as the block? True? Where motors not built with all matching date codes?
5. I found the production tag on the motor and it states the following 390 69 9C K 384 T From what I've read this is correct to the motor but I am wondering since the block and heads are a month older than the production date, is it correct to say that 9C (March) is when they assembled the motor from those parts and the car itself as per the tag?
I appreciate anything you all can provide! Pics attached of Block date and production tag
CJ
69 Mach 1 390 4spd San Jose 3-28-69 Acapulco Blue