To find out, you'd likely need to consult multiple resources, including:
* Dodge historical records (if accessible): These may be available through the Stellantis Heritage Center (the successor to Chrysler's heritage division), but access may be limited or require significant research.
* Collector car databases and registries: Websites and clubs dedicated to classic Dodge Challengers might have aggregated information from various sources, providing estimates. However, even these are rarely perfectly precise.
* Original build sheets (if one exists): A build sheet that came with a specific car would state the exact specifications, but these are rare and not available for the vast majority of cars.
In short: You won't find an exact number. You can only find estimates through extensive research across various sources.