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Authenticity reference

Scheduled production date relationship to date-coded components

date correctness · reported

1969 Plymouth Road Runner Hemi at Orange Julep; Hemi-labeled show-field visual context. 1969 Plymouth Road Runner 426 Hemi

Reference Details

Common issue
Treating same model year or visible component appearance as enough, instead of checking component dates against the car's SPD.
Confidence
reported
Correct value
MMC date-code guidance says component dates should be evaluated against the scheduled production date; it reports a normal engine casting-to-SPD range around 30-90 days, while Hemis have been found as much as 8 months before SPD.
Where to check
Scheduled production date on build documentation/fender tag, engine casting date, and other component date codes on the individual car

Cars With This Authenticity Marker

1 linked car page.

Sources & Documentation