That dyno figure does not sound right. My 32 GTR is running at 160kw at all 4 without aftermarket exhaust or cat. Have been told that is poor too! A lot of car that come out of japan run to rich. What is fuel comsumption like? Should get at least 400 to 450 out of a tank. $5000 to get to 200kw is a joke! If you have a good exhaust, hiflow cat, HKS cam gears and a good tuner you should be able to make 200 to 250 with a bit of extra boost.
Call Ben (racepace motorsport) in Melb. to set you on the right track (0397629421). A 500kw at wheels R33 GTR is all the qualifications this guy needs!