You don't normally bore a block to gain power, boring is done more to provide a smooth and perfect surface for your piston rings to seal.
I would recommend sending the bare block to a machine shop who specializes in this work and go off of their recommendations. It may be that a cylinder is beyond repair and will require even more than a simple bore job (i.e. sleeve)
"I'm not driving too fast...just flying too low"
-03 SB Cobra vert- 2552 of 5082 Born 02/25/03
90 7up vert - new project-07 DSG Focus -DD