My 1970 Challenger RT/SE 440-6 has recently undergone a 4.5 yr OE restoration and when/where needed I found date correct (matching) parts. But depending on the part, i.e. exhaust manifold, wheels, etc. the date codes that are acceptable are 30, 60, 90 even up to 120 days.

With today's digital technology, I would think it would be much easier to track every part installed on every car and was just curious if the date correct parts are in tighter control.

But for the sake of this question, let's say, for example, if someone wanted to restore a HC Redeye in 40 yrs from now with date correct parts do you think the date codes would have to be a lot closer together?

Does anyone know any auto assembly people out there who could verify if the standards are tighter now?

Thanks

That is interesting, and I think it would depend on the part.
With JIT, just in time delievery and not stock piling parts, you would get fairly close to the assembly date.
but there are going to be some parts that either have a long lead time, or would be required to be made in a min batch setting.
in those cases, you could be out that 30, 60, 90 and even longer for the date coding.

you will recall some assembly lines shut down due to a shortage of parts.
They also may have decided to adjust for that too.

shipping would also play a factor in the lead time. how long do parts take to get here from japan or wherever.

My T/A was scheduled for 4-17-1970

The final assembly date on the original engine was days later, so for whatever reason the car was built later than 'hoped for'.

Three windows dated to June 1969, they were the oldest date coded parts I found on the car.

Some of the seat belts were 3rd 1/4 of 1969.

So if the parts originally came on the car, they are date code correct for that car.