Exducer / Inducer OD : 37.7/45.0mm (MAMBA IHI RHF4 VG16 PRO Turbine Wheel). MAMBA 1819 Honda 1.5T IHI PRO RHF4-4151 Turbo Upgrade Kit (Compressor wheel + Turbine wheel + Repair kit) +40% Air flow. Compressor wheel & turbine wheel Balanced by Schenck already.