Two main features of the MAC-hs protocol of HSDPA are retransmissions of erroneous blocks and in-sequence data delivery to the upper layer. The first function is fulfilled through the HARQ mechanism. The second function is achieved by managing transmitting/ receiving window and by using a specific numbering. This paper analyzes influence of MAC-hs window and release timer settings on the wireless transmission delay. Simulations show that the parameter setting has to be advisably set up in order to prevent an unnecessary increase of wireless delay.