You can't say that 500whp will take it out of the efficiency range by itself. Maybe boost, ok.... If I need to run 27psi to hit 500whp then mabye, but according to this 27.5psi could be had in the midrange tapering to 19psi or so at redlline. What this translates to in HP yet I won't know till the turbos go on but it is DEFINATELY possible to peak OVER 21psi and still be on the island.
99 Eclipse GSX dyno numbers soon
12 Maxima Slow
03 EVO 8 600HP Sold
09 e92 335i 440hp Sold