The conventional wisdom on these blocks is .060" over is dependable street max. More has been done and has worked well for some. Check Leo's book where he talks about core shift. Find some cheap 327 pistons (piston) and check clearance. It was not unusual in the past to knurl the piston skirt to get a closer fit. If you can play with it for little money it may be worth it. If the cost is more than other options it would be best to start with another block and build it other specs. Otherwise you will end up as an old man sitting in a pile of parts that fit nothing you ever wanted to build.
