Custom/Hybrid what kinda prop and pump would do best ?

[California-66]

hey friends ,some people told me that 144 Magnum setback "the one i have now" would work best for my 1000cc if it is pitched right ,.. my prop is 15/20

and i need a monster bottom end ,. i dont need the top end at all

so what you guys think ? what should i go for ? 12 vains or 14 vains .. 148mm magnum ? and what kind of prop will work with me ?