lt1zpwr

hey guys, my friend also has an lt1 and he has been having some probelms with misfire. at first he was getting a random misfire code after he had already put in new plugs, wires and injectors so he took out the opti and the cap and rotor were messed up so he replaced them. after this the car no longer had the random misfire code but u could stil tell something wasn't right it was lacking power so he hooked up a scanner and it sowed under the misfire data that cyl 2 and 7 would miss every once in while. he has now removed the opti and purchased a new one and is currently installing it, if this dosent work what else could be wrong? thanx