Ideally track the day after a heavy weights day is not optimal, unless you're in some kind of insane overload block. Best use of a track day (especially one where you are doing sprint efforts) is to come in fresh so as to get the maximum benefit from it. I try to keep my gym days spaced at least a day apart from a serious sprint effort day, unless I'm doing two sessions in a day, but in that case I'll try to do the bike work first, then the weights either immediately after (making it essentially one session) or at least three hours after the track.