
VIN Numbers
This page will be of little practical use to the reader unless he or she has access to the Plymouth SuperBird NASCAR Race Program Serial Number List. This list was prepared by Chrysler as part of the documentation used to prove and record compliance with NASCAR's homologation requirements. A nicely bound 80+ page photocopy of this interesting document is available from the DaytonaSuperBird Auto Club. Included in these pages are 1,920 SuperBird serial numbers (not in numerical order), as well as the date each car was was shipped to the Clairpointe PreProduction Facility and the date of shipment to a Chrysler dealership. This is valuable information for those wishing to determine a very specific build date for their car. The telegram from ACCUSFIA to Chrysler indicating their satisfaction that Chrysler had produced enough SuperBirds to "legalize" that body style for NASCAR competition is also included. Information about the club, including its address, can be found on the Clubs page. The cost of the serial number list is $17.00 postage paid. There are 21 sets of duplicate serial numbers on the list and they are presented below. The duplicate numbers are divided into five groups to aid in clarifying this discussion. The terms "VIN" and "VIN number(s)" both refer to the serial numbers and are used interchangeably in this discussion. Group I
Group I  The repeating VIN number pairs listed above seem likely to have been repeated by accident, i. e. apparently caused by clerical error. The numerical portions of the serial numbers are identical, as are the letters indicating engine type. Also, these identical VIN numbers are consecutive as listed in the Serial Number List. Lastly, when the VIN list is placed in numerical order by VIN number, there are no nearby "skips" in the sequence (with one possible exception, the # 1244/1245 pair). When there are skips near a repeating pair, this might indicate that one of the two repeated numbers is the skipped number, meaning that one or two digits were recorded incorrectly rather than the whole VIN having been recorded twice by accident. The # 1244/1245 pair follow the "skipped number" 173756, but it seems more likely that one of the two from the #1239/1289 pair discussed later could be this skipped number. If the conclusion discussed above for the six pairs presented is correct, then the net effect on the SuperBird production total is to subtract six cars from the count. Group II
Group II  The three pairs listed above fit the description presented in Group I, with the obvious difference that they have different engine designations. When these pairs are viewed with the VIN list in numerical order by VIN number, they are part of a long sequence of "U" code cars. One could therefore conclude that the "R" code numbers are incorrect, due to a typographical error. Or, these were in fact "R" code cars and the "U" codes were included by error for some reason which is related to the fact that these VIN numbers fall into long sequences of "U" code cars. The net effect is to subtract three cars from the SuperBird count. Group III
Group III  Although not consecutively numbered in the VIN list, the pairs listed above meet the other conditions discussed in Group I above. They are apparently repeated VIN numbers, due to some type of clerical error. The net effect is to subtract three cars from the SuperBird count. Group IV
Group IV  Numbers from these pairs do not appear to be clerical errors repeating an existing number, but an error in recording one or two digits. When the VIN list is placed in numerical order by VIN number, there is a "skipped" number very near where these duplicates appear. One conclusion might be that a number was mistyped by one or two digits and one of the pair is in fact the missing "skipped" number. This conclusion has no effect on the SuperBird count. Group V
Group V  These last two pairs are not near any "skips", and may have simply been caused because of the similarity in appearance between "U" and "V" when these numbers were transcribed. The net effect on the SuperBird count is to subtract two. When placed in sequential order by serial number, the Plymouth SuperBird NASCAR Race Program Serial Number List contains several long runs of serial numbers with one or a few numbers missing, leading to the obvious question  could the cars with these missing serial numbers be SuperBirds also? Apparently so, as the author has confirmed five SuperBirds that carry VIN numbers coinciding with those missing numbers. To be included in the list of missing numbers, it must be part of a "significant" sequential run. A missing number is part of a "significant" run when it is preceded by one number and followed by two, or preceded by two and followed by at least one VIN number that are sequential. This ignores the possibility of missing serial numbers that fall at the very beginning or end of "significant" sequential runs, as well as those that might be associated with a series that have only one or two members. Using this approach, 47 missing numbers were located. Some of the missing numbers are probably a result of typographical or other errors discussed above, but it seems likely that many of the 47 may actually be SuperBirds. 