One of the first processing steps in a DVB-S2 signal receiver is the detection of frame's header. Recently, an architecture using only the phase information of the received samples was proposed. In this paper several optimization in algorithm/architecture are proposed, leading to better performance and reduced hardware complexity. For an SNR of -3 dB, the probability of miss detection of the header detector is reduced from 0.7 down to 0.52 for a constant false alarm probability of 10-6.