Hola b377 -
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As to which engines on that AF -328, in 1972, it would certainly have the latest dash number (JT4A-11) at that time, these had 17,500 lbs of thrust each, and the maximum gross weight was up to 312,000 lbs. They were guzzlers, but had adequate power. Funny is, their performance was great at higher levels above FL350, whereas the JT3D fans "ran out" of vitamins and ideas above FL350.
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With PanAm, I recall we had fuel flows in cruise close to 16,000 lbs/hr for the 707-321/331, while the 707-321B fuel flows dropped below 13,000 lbs/hr. To my opinion, the 321B were better airplanes especially on takeoff, thanks to their better flaps settings and leading edge devices.
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The 707-100 and 720s, with their JT3C were merely converting fuel into noise and smoke. I never flew the "Water Wagons", I recall that pilots telling me flying them for a "wet takeoff" hated their handling when the water injection quit after takeoff at "uneven times"... making the pilot believe that they had an engine "failure" on the left side, then a few seconds later, on the right side, this repeatedly until the water tanks were all empty.
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All pilots loved the 720B... the race horse, even taking off from La Paz, Bolivia. PanAm inherited some ex-Lufty 720-030B, but did not keep them long in operations.
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Thank you b377, for forcing my old brains to recall these great planes.
Happy contrails