MPC is not going to split. Why would they (the company) have a buy back of shares going on? They are trying to reduce the number of outstanding shares with their buy back. A split would completly go against that. It would double the number of outstanding shares. Don't look for a split.
I do believ it will be in the high 90's or low 100's by the time summer demand season gets here though.
Buy all you can and enjoy the ride. It's here to stay for a while.