You need a 440+ CI to make that .484 cam a viable choice IMHO... 383's have short strokes (even shorter then some small block chevys ) So they don't make much power till they get up closer to 3K rpm anyway, now add in a cam that is not known for great low end power in that same 383 and you can see where the weight of a b-body is NOT going to help things. 383's are fine in b-bodies, but understand what you're working with. it's a big block that was born with a lack of stroke and is super easy to over-cam