I found this on a newly re-opened post on here, wondering if this is the answers we're looking for?
As for the 383's hp it goes like this:
In 67 the 383 in the Darts and Cuda's had the small exh valve (1.60) heads and the restictive exh manifolds along with a small 383 cam and the hp was 280.
In 68 the A-body 383 got the 906 heads with the larger (1.74) exh valves and the hp was raised to 300 hp.
In 1969 the A-body 383 got the larger 383 Roadrunner-SuperBee cam and the hp was raised to 330. The Roadrunner 383 was 335 because it had better flowing exh manifolds then the A-body 383.

I'm the CARETAKER of Weinstats '69 440 'cuda registry and have 104 of the 360 cars to date. 84 fastbacks/20 coupes. Always looking for new(REAL M-code) '69 440 'cudas to add to the registry so drop me a note if any are found or known. This isn't a publicly released registry. Thanks, Dave