I believe someone else with new turbos (maybe Vargas maybe not, there is a bimmerpost "vow dude, respect"-wise thread on it) just recently recorded 700+ whp with N54 (a 335i). So, sky is the limit, almost literally.
Does this 650 whp kit also come with a free pass to a nearby runway? Would make more sense
__________________
"The mark of a great car is one whose overall competence exceeds what you should expect from its individual components and the 1M does just that", Chris Harris.
BMW 1M-SOLD-: TECH: Evolve Race+N55mids, Evolve IC, Michelin PSS, ER cp, aFe filter, CDVx, Vorshlag camber plates, BMS OCC EXTERIOR: trunk spoiler, blacklines, black grills, IND goodies INTERIOR: Alcantara steering wheel, steel pedals, custom mats, MPower e-brake.