You could have a look at these folks.....they seem to be offering something for the N52 engine. Not much gain in the hp or torque though, for the money at least.
'11 Z4 30i (Sold!);'11 X3 28i (Sold!); '15 M235i (Recalled/Crushed!); '15 28i X3 loaded; '14 x328i loaded & Mineral Grey '16 M235i Perf Edition, Dinan Stage 3, CAI, FMIC, Res-Delete