I'm pretty sure that you could get something better on there is all i'm saying. those 6.5 turbos from what i have seen aren't the most reliable little things out there. for the price, why not use it right? I just think you could get an HX35 to spool good and probably flows a lot more CFM.. Maybe even the turbo off a later model common rail cummins. they flow a lot of air(good for 500hp in a cummins) and have a really tight turbine housing(9cm)... They are also reliable as hell.

I'm just trying to throw out ideas man.. not knocking your setup. it works and if thats what your stuck on then awesome. Ideas never hurt anyone though.