Pure stg2 here. I would think running 98 octane you could run higher boost, closer to 18 psi or more.
Currently running almost 19psi at redline but I am running E70 with Fuel TBI. Still dialing in the tune. Once dialed in I am looking for 25-26 psi.
Did you get the pure inlet? The stock inlet gets pretty restricted right at the turbo connection.
This turbo feels amazing.
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N55 135i DCT, Pure Stg 2, JB4 map 7 E50, N54tuning Catless DP, VRSF 7" IC, VRSF CP, AFE sealed intake, Ohlins R&T, Voshlag camber plates, corner balanced, M3 front control arms, M3 FSB, M3 RSB, M3 rear subframe bushings, M3 rear wishbone, RPI quad exhaust, APEX Arc 8 wheels, Fuel-it stg2 LPFP- Fuel lines- E sensor, BMS OCC, Quaife LSD