See....Camshafts and converters go together. His .509" works well with a 3800 stall converter and 4:30's. That's not a "bump up a bit" for your 383. That's a huge leap. Respectfully.

Use caution on the cam choice. Even the factory used a higher stall converter when they used the "HP" cam in the 335 horse 383 and HiPo 440's. And that's a small camshaft by todays standards.