if by "tune up turbos" he means get new turbos, injectors and intercoolers... then yes
With the Jim wolf "Stage 3" kit you get a cat-back exhaust, an intake, an upgraded ECU and a set of bost jets which will raise the boost from 9 psi to around 14. This supposedly gives around 400 flywheel horsepower. However, most "Stage 3" Zs dyno around 315 hp +- 15 hp, which leads me to believe that the crank hp #s are a little lower than jwt estimates.
But, these mods should get him around 385 hp at the engine.