Trying to find out what date codes would be considered correct for a car built Dec 17, 1970 at the St. Louis plant.

RP23N1G.....
Parts that I am trying to narrow down....
383 block
383 hp exhaust manifolds
15x7 rallyes

There is no way to know the actual build date.

So, if those original items are missing from your car, there is no way to know what dates they had.

They could be before, or after the scheduled production date on the fender tag / broadcast sheet. That date is the day they hoped to build the car, but several examples of early / late built cars exist.

If your original Mylar door sticker is still present, it will show the actual build month.

Just says.....

Just trying to figure out a general idea of what part castings and numbers would be considered "correct" items for the car.

Did you buy it as a shell, or are there other parts that you can check? There are lots of parts on the car that are date coded, so if you start looking at them you should come up with a range.

If not my general rule of thumb is 2-4 weeks before they mylar sticker.

It is a mostly complete car. (Check general forum, "They are still out there Chapter 71) However the original (and even a replacement) motor were both "blown up" and MIA by 1978. At that time the wheels were still on the car. The guy agreed to buy the car and went to get the money. By the time he returned. He said the wheels (trim rings, centers and front buckets) were gone. Anyway I am trying to gather the major parts since it seems to be an unusual optioned car.

I found the correct air cleaner. Now just trying to track the other correct part numbers and castings that would have been correct for it.

The "A12" crowd has found the K-frame date to be the closest to actual production day - it seems to make sense on the 1969 Lynch Rd. built cars.

So the motor is history. A date code then is only important to someone that has bought into the 4 week or so thing before the build. There is only one VIN to One Block. So if your motor is history why not build a stroker motor. No one will know unless they crawl under your car with a mirror and look at the casting numbers and dates. You can build at least 500ci out of a Low Block big block by using the 400 block and a stroked crank. There are many smaller CI motors under 500 CI that can be built by using a 383 block or a 400 block. No one will know when your ahead of him on the drag strip or street. If you want a 383 near your build date you might also be buying someone elses original motor.

By the time I find and buy all the hard to find (expensive) parts that are missing. There will be no money left for a stroker motor! Just trying to put it back as close to stock (as it left the factory) as I can get.

Correct, but non-leap year 3410 = Monday, December 7, 1970

I would use that date as the base in looking for other dated parts.

I found a 383 block that has a casting of 10-19-70. Probably going to go with that and call it good.

Have no idea on the assembly date?

It will never be a #'s matching car and I am fine with that. But I figure a motor cast near the same time as the car would be worth looking for rather than just sticking in some random year block. I mean after all it is a Satellite Sebring Plus. Having a close to correct motor should add at least $50 to the value of the car!!

John's talking the engine's assembly date (EAD) located on a pad below the distributor G 383 12 2 HP or similar. Also, what is the partial VIN on the engine?

Thanks for the info! I will check the next time I get in touch with the guy who has the motor. I will post pics when I get them to verify.