1974 VINs from Newark Assembly

[PeugFra]

Come to think of it, the low number of PK cars and the total absence of pursuit cars in the 1974 Newark C-body production could well be the reflection of a very trivial fact:

It seems that a lot of Plymouth Pursuits and Patrol units and Fleet orders were built in May. That seems to be standard SOP for MoPar fleet orders.

If this Schedule of Production for MY 1969 applied to MY 1974 as well, at Newark they just didn't get around to filling fleet orders, as their production had ended by the end of December 1973.

 

[69CoronetRT]

Come to think of it, the low number of PK cars and the total absence of pursuit cars in the 1974 Newark C-body production could well be the reflection of a very trivial fact:




If this Schedule of Production for MY 1969 applied to MY 1974 as well, at Newark they just didn't get around to filling fleet orders, as their production had ended by the end of December 1973.

There is no way to prove either hypothesis without factory records. Therefore, the assertion ranges from an interesting thought to a guess. Neither of which is helpful to you.

An equal number of fleet cars could have been built in any other single month but they do not survive leading to an erroneous conclusion that more, simply because they survived, were built in a month.

You can’t prove a negative. Your evidence may not exist.

When doing research on your topic, trust your own evidence.
Learn what SOP was for Chrysler and your plant of interest.

 

[Fury Pursuit]

I am having a difficulty understanding the point of this post/thread.

What is it?

 

[PeugFra]

The idea is to find out whether 1974 C-body production at Newark assembly somehow differs from Belvidere production, as far as this can be determined by looking at the VINs.

 

[Fury Pursuit]

What differences are you looking for?

Build process, assembly, paint application???

 

[PeugFra]

Any difference that can be established by looking at the VIN, for now. Let's not pretend too much! That would be

trim level: L/M/H/P/K/T
body style: 23/41/43
engine: K/J/M/N/P/T/U

(Actually I found no J-code engines in Newark VINs; all J-codes I found were produced at Belvidere for California. The geography principle applies here.)

If you have information that goes beyond these three criteria, that would be great!

 

[Fury Pursuit]

I understand now. Thank you.

The production of like or same vehicles does differ from plant to plant.

The difference your are going to find in a VIN would be self explanatory.

You need to examine actual, same cars from differing production plants or look at the assembly engineering drawings from each plant (which differ from plant to plant) to see any actual differences in the car.

Same make and model cars made in different production plants are assembled differently. Although the differences are small, they do exist.

But I'm thinking you are after "what cars were built at what production plants, and which were not" based on a VIN, so this information isn't useful to you.

Best of luck with your research!

 

[PeugFra]

When doing research on your topic, trust your own evidence.

You couldn't be more right! In want of factory records I will give it a try with statistics. As I worked this out, the write-up became rather complicated and tedious. Sorry for that!

To test the assumption that fleet orders are randomly distributed over the production year, I will compare the total available sequential production number space with SPNs of fleet cars actually found. As survival rate has no relation to SPN space, a statistical approach is legitimate.

Fleet cars are DK/PK cars, non-DK/PK cars with the high-performance P- or U-code engine and other cars included in equipment sales by a public entity. The sample derives mainly from newspaper archives and is possibly biased against examples with the U-code engine, because I only found equipment sales by non-state entities (counties, cities, townships ecc.). As equipment from one and the same entity tends to have consecutive SPNs, most data in the raw sample (144 cars) are not independent. They are groups (orders) rather than individual cars. The corrected sample eliminates these dependencies by considering just one SPN for every group of consecutive SPNs found. I will count orders, not cars.

I calculate the total SPN space for Monacos and Furys by subtracting not only the Chrysler Town & Countrys but also the Monaco/Fury wagons, all produced at Belvidere:

Total SPN space: 59,300 Newark + (157,720 - 8,194 Town & Country - 29,622 Monaco/Fury wagons) Belvidere = 179,204
Corrected sample: 17 DK + 10 Monaco other + 29 PK + 18 Fury other = 74

The wagons need to be excluded from the comparison, because for them there is nothing to compare: they were all assembled at Belvidere, at the same time reducing the SPN space relevant to the comparison.

Now I divide the total SPN space and the corrected sample in two groups: group A with an SPN up to 59,300, which corresponds roughly to the months August - December 1973 ("early"), and group B with a higher SPN ("late"). A complication here are the 8,194 Town & Countrys, for which I only have a very small sample (11), mostly with SPNs below 59,300 (8 out of 11). I choose to err on the safe side and subtract them all from group A, thus artificially changing the proportions in favour of group B. A similar problem is posed by the Monaco/Fury wagons, only here the sample is large enough (49) to allow for a rough estimate of their distribution:

Monaco/Fury wagons sample subdivision
A (early): 23
B (late): 26

For now I will subtract half of the 29,622 wagons (14,811) from group A and half of them from group B:

SPN space subdivision
A (early): 59,300 Newark + (59,300 - 8,194 Town & Country - 14,811 early Monaco/Fury wagons) early Belvidere = 95,595 (53.3%)
B (late): 157,720 Belvidere - 59,300 early Belvidere - 14,811 late Monaco/Fury wagons = 83,609 (46.7%)

For Newark it is known that C-body production ended in December, 1973. For the approximate dating of early Belvidere Monaco/Fury SPNs I can offer PM41U4D158482 with the SPD value C10.

The upshot so far is the insight that, would the distribution of fleet orders have been random, one would expect about half of them to have been executed by the end of December, 1973. Now consider this:

Corrected sample subdivision
A (early): 1 Monaco + 10 Fury = 11 (14.9%)
B (late): 26 Monaco + 37 Fury = 63 (85.1%)

Running a Goodness-of-Fit test on these numbers, ie. comparing the expected distribution in the total SPN space with the distribution in the corrected sample returns a significant result at p < 0.01.

In other words: the corrected sample rejects the assumption of a random distribution over the production year. And that's where the story ends. For an accurate estimate of the actual distribution of fleet cars the raw sample needs to be enlarged by a factor of 2.5, something I do not think will be feasible.

 

[69CoronetRT]

.....raw sample needs to be enlarged......

BINGO.

This is another reason WHY every car possible should be documented whenever possible. More data leads to better analysis.

It’s hard enough to collect data on A, B and even E bodies that were produced in much higher numbers. C body data of all kinds is really hard to find. You are trying to piece together info from a small volume plant producing a low volume car from an “off” year that no one wants to save anyway.

I salute your effort and wish you nothing but the best.

 

[PeugFra]

Once you accept this line of reasoning, let's push the idea of expected distribution around a bit.
The Goodness-of-Fit test is useful for identifying wrong assumptions, but it does not help much in selecting a correct assumption.

With this limitation in mind, I can dream up a whole series of assumptions on when fleet orders were built that are all rejected on the basis of the above sample subdivision.

The most extreme assumption that is still rejected by the test at p < 0.01 is 28% of fleet orders in group A (early) and 72% in group B (late). So the proportion of fleet orders is at most 27% in group A and at least 73% in group B.

Now what did Fury Pursuit say?

It seems that a lot of Plymouth Pursuits and Patrol units and Fleet orders were built in May. That seems to be standard SOP for MoPar fleet orders.

 

[PeugFra]

Newark-built cars usually didn't get shipped to California. Too far away! But still I found a bunch of Newark-VINned cars advertised in California newspapers. They were all offered for sale at a discount when the 1974 model year was just finished, during fall 1974 and winter 1974/75.

Curiously enough, these offerings all have the 400-2 engine (M), although only the 400-4 (N) was approved for new C-bodies to be sold in California.

Was there some loophole to the effect that once a car was out-of-model year (but still new) the CARB rules did not apply anymore?

 

[PeugFra]

Correction: These were "Special Purchase Chrysler Corp Lease Cars" that had been bought by several California dealers to be sold as used cars. No new cars involved here.