Stronger fuel pump, some type of boost dependent fuel pressure regulator, BOV, sometype of wastegate, necessary lines (fuel, oil feed/return, etc....), gauges, there's more but can't think of them right now.
__________________
Olympus Evolt E-510, E-520, E-30 x 2
11-22mm f/2.8-3.5 Zuiko Digital
14-54mm f/2.8-3.5 Zuiko Digital
35-100mm f/2 Zuiko Digital
50-200mm f/2.8-3.5 ED SWD Zuiko Digital
Cybersync wireless trigger
FL-36R, FL-50R, Metz-48, and Vivitar 285HV x 3