Measurements of the differential cross-sections of the (π−,3He) scattering at 68 MeV, of the (π+,4He) scattering at 120 MeV and of the (π−,4He) scattering at 174 MeV are presented. The experiment has been carried out by means of a high-pressure self-shunted streamer chamber filled with helium and triggered by a hodoscope of scintillation counters. The elastic differential cross-sections have been measured and the results are compared with the optical-model calculations. A new estimate of thef2(π3He3H) coupling constant is also presented.