350 LT1 compression...Lower it?

[TDW]

I took the engine from my 70 Z28 to the machine shop. It needs .030 over pistons. I bought a set a while back. TRW, GM replacement pistons. The engine builder wants to cut the pistons compression ratio down to 9.3 to 9.5. I don't drive the car too much,so I am thinking about leaving them at 11.1 and running a Crane Blueprint Series factory spec LT1 cam. Any thoughts are welcome. What have you guys with this engine done at rebuild time? Engine builder says it won't run on 93 octane, but my L78 and my 302 both run good on 93 pump gas.