First off, numerous built cars are taking that stock throttle body to the 550-600hp mark without choking the motor too badly.
Secondly, do a search and find the pluthera of posts regarding trouble getting the throttle body to work properly. Not just BBK's either, it's a sporadic issue with all the manufacturers. Here's a search:
I will let you know Saturday how this one works out. It seems to be working fine but there were also 50 other codes from the VCT and other stuff that caused the check engine light. We set it back to factory voltage with the dealership computer and as of now we do not have any trouble codes caused by the throttlebody. So will update you Saturday on the status of it. It is a Black Diamond mono blade and all we did was make sure that the return spring was reinstalled in the right location and it full closed under spring pressure alone and not having to use the electric motor.