w/ robert but want to add a few points. It's going to want more than a 650 carb, upgrade to a 750, my suggestion would be a holley 3310 vacuum secondary carb, and please invest in a tuning kit to get it dialed in correctly.

Which cam do you have? Do you mean the comp xe274h? That cam in an aluminum headed 383 would want more like 10.5 compression. With 9.5 compression it's going to be a little soft on the bottom with that cam. And it's going to want to rev. IMO not the best cam choice for running hp manifolds. A lot of members have had good success with the comp xe268h in their 383's, you might want to think about doing that cam intead, especially if you really want to run the hp manifolds instead of headers.