In your 02, stock rods/stock heads, you are pushing your luck at 35+ psi boost and or 400 HP. If you are serious about 50+ psi boost (boost doesnt = HP btw) then you are going to need what Luke suggested and that is an entire build from the crank up. Head studs (maybe head o-rings too), forged rods, fuel system, high pressure oil system, turbo upgrade, injector upgrade, and PCM reprogramming. Dont forget that your going to have to build up the drive train to get it all to the ground too.
But it sounds intersting, keep us informed on what you got going on. Theres a couple of the guys here dabbling in high HP PSD's right now. So, there is some good knowledge here.