I'm thinking I put too small a cam in my 360 Magnum...

Well, if I we’re going to recommend a shelf cam for this and it’s a hydraulic flat tappet then I would say this grind. It’s the limit of what 3.91 gears and a shelf 3500 converter would like but would bring out the best of everything when you sprayed it.
Howards Cams 716771-08 Howards Cams Hydraulic Flat Tappet Camshafts | Summit Racing