im currently looking at getting into and rs and have realized that in 99 they switched to a sohc. im looking at 98s 99s and 00s. is there any one year that is better suited towards tuning, mainly, if the breathing of the 98 is addressed will it then out power the sohc? also, how much does the 00s limited slip diff. help the handling? are there any other year specific differences you can tell me?