Single pane vs Dual pane

Mopar Muscle also did a 400 build up that cranked out 400+ HP with zero deck pistons, Comp Cams Xe268, Weiand dual plane and a 750 Holley.
Then a swap was made to a T-Q and MoPar single plane M-1 and made more power across the board in torqe and HP beating the dual plane everywhere.
For the 383, I would suggest the next cam up since it is a tad smaller and the 400 in the build just cleared 400 hp.