The most extensive chronometric study ever undertaken on Egyptian Dynastic sites was published in Radiocarbon by Bonani et al. (2001). It comprised 269 radiocarbon measurements on monuments ranging from the 1st-12th dynasties. However, many of the calibrated dates obtained were significantly offset from historical estimates. The greatest discrepancies occurred in the 4th Dynasty where, paradoxically, the dating program had been most rigorous. For this period, 158 measurements were made at 12 sites, with the majority of the dates being 200-300 yr older than expected. The 4th Dynasty results were especially significant as they included some of the most important monuments in Egypt. In this paper, the raw data from that study have been reanalyzed using the OxCal calibration program, making particular use of its new outlier detection functionality. This Bayesian approach has resulted in a new series of calibrations that show much closer agreement with conventional chronological records.