340 Cam
@krazykuda has a lot of time and work into these specs. The information came from factory service manuals. Thanks Karl.
Factory V-8 Engine and Cam Specs by Year 1965-1975
Those are gross duration figures, not duration at .050.
I would note that CamCraft's "advertised duration" figures for Mopar cams don't agree with Chrysler's own advertised figures. I'm thinking that CamCraft's "advertised duration" is using a different base lift to measure duration from than Chrysler did. I remember Chevy cams of the era had what looked like huge durations - 300 plus degrees - much more than similar lift Chrysler cams. But that's because - as I understand it - Chevy measure the duration of their cams at zero or near zero lift, while Chrysler measured their durations at (I believe) something like .006 lift. Going by memory, so I might have my numbers off, but there was a significant difference between the way Chrysler and GM measured their cams' durations.
Even Chrysler could play that game. There were a couple of Chrysler Corp. ads in the late sixties that bragged about the HP 440 cams having something like 284/292 duration, and some have thought this was a totally different cam, when in fact it was (I believe) just the regular hi-po 276/284 440 cam measured from a different starting point.