Just got back from EFI for a quick retune after a pulley swap... I went from 581hp / 536 ftlbs on the 3.0" to 612hp / 554ftlbs on the 2.9". Boost went from 18.3# to 19.0#. These are all corrected numbers on the Mustang dyno, with 17.5 degrees of timing and 93 octane. The Cobra actually put down 634/574, but it was only about 55 degrees outside....makes me want to post the uncorrected numbers (but that would be cheating, right? ) Anyway, just a data point for you KB / Whipple guys if you are wondering what that "next size down" would do for you. It surprised me that .1" diameter gave me 31 more hp and 18 ftlbs, but I'm not complaining! Just wanted to hit that magic 600 number on the conservative Mustang dyno, so now I can say I'm done...for now....:beer: