New observations of BS and BT Cnc were performed during the STEPHI VII campaign in 1996 February. An overall run of 115 hours of data was collected. Different methods have been used to analyse the time series, bringing the detection of 2 frequencies for BT Cnc and 3 frequencies for BS Cnc above the 99% confidence level. A comparison with the literature reveals that the dominant mode of BT Cnc ( ~ 9.8 c/d) has kept excited over tens of years, while the secondary modes have not been the same all the time. However, during the very last years the two frequencies detected by us have been the only ones noticeably excited in the spectrum.