C5 rear mount turbo question?

[rthackwray]

I have a 1998 C5 corvette with 232/234-112 lsa futral f14 camshaft,low lift..I believe 585 lift on each side.The car is 4l60 with Circle D 3600 stall and 3.90 geared.I recently added a rear mount 76mm turbocharger with intercooler.I am using stock manifolds with vbands welded on and entire turbo build is fabricated.My heads are stock and unmolested.I believe 806 castings but do have the valvetrain upgraded with dual springs,etc.Intake is a stock ls1 and TB is a bbk 85mm with spacer..My question is..Will I be able to achieve over 550 rwhp with this combo and rev it to 6k even with the positive overlap of the camshaft?My car is at the tuners at the moment..The car is dropping off drastically on power @ 5k rpm at only 5lbs of boost.The fueling,afr, and pressures are ideal as my tuner tells me.Any and all info is appreciated.I just want my car to at least rev to 5700 before dropping off.I believe the cam is rated for 6500 rpm.Its being tuned on E85 and has walbro 450lph e85 pump with hotwire and siemens deka 80lb high impedence injectors.Thanks guys