I don't think you will. It would be close but not 400+

 

whenever you port the turbine housing it does help. If you don't currently own a 10.5 housing, then i would not do it. If you do, and plan on down the road switching to a larger stock frame turbo that can use that turbine housing then its well worth it!

After I had my housing ported i felt a pretty noticeable difference on how the turbo spooled up and hit harder downlow.