Shawn, if the motor I spec'd has 8.5 c.r. now, with 72 cc chambers, then a swap later on to 64 cc heads (Vortec or whatever) would give a c.r. of 9.33:1.

As far as your question about a stock cam spec, I suspect the cam with this crate motor is about as stock as they come. Chevy might offer a milder cam, but it won't be by much.