With the intercooled Vortech kit with 9psi boost, you will make the claimed 460kw's quite easily, with the tuner etc..
To make the 400kW's at the wheels, i would consider upgrading to the Vortech V-2 T Trim, running 11psi boost.. We do a complete kit and it is $15,995.oo it will produce 525kw's @ engine...
I would also consider upgrading engine internals at this power output..
If auto, you definately need this addressed, as far as enhancement kit etc...