What goodies do I need to build a Fast slant 6

This
A big pile of cash!
and a whole lot more.I went the normally aspirated route with head work, offset ground crank, light weight rods,pistons and crank.Whole ball of wax cost me right around $14K Why ? cause I wanted to reach 325 HP but was shy and made 308 if I remember.That was 16 or so years ago.