360 help

The thing that sticks out most to me is the intake.
I would try an intake swap first. The Performer is killing you.Go to a RPM or Air-Gap.
If you have the Thunder series Ede AVS 650, that should work well.
Your motor can handle a 750 cfm as well.
Try the intake first. Should be a whole different beast.

If you decide on a different cam, I would stay away from the Ede.
Go for either a XE 268 or XE 274 Comp cam.