you'll need a fuel system that can keep up with the higher concentration of air, and an upgraded map sensor if going over 11lbs and a good tune on the ECU. stock sleeves can handle ~13-15lbs of boost but no higher because the top of the sleeve will begin to expand and crack due to the added stress load on an open ended block. also check compression to make sure the head and head gasket are still good, and that everything on the motor is in good working order.