Don't get real hung up on compression. Remember, it's only about a 3% increase from one ratio to the next going up, so that's not where the most power is made. All these guys around here will have you running on the ragged edge of detonation if they have their way. I would concentrate on getting a GOOD port job done on those heads. That in and of itself will add more than going up one compression point. A 9.3:1 small block with good flowing aluminum heads and EFI can make a lot of power. If it's a street car, the very last thing you want is to be fighting detonation sitting in traffic with heat soak.