Compression Calculator

I called and talked to Ken and he wouldn't stray from his original recommendation. I was talking to my dad and he has a cam new in box that never got used for a small block. What are everyone's thoughts on this one?

Again here are the engine specs:
68 340
KB 243
Edelbrock 63cc heads
273 adj rockers
4 Speed
4.10 gears
25.7" tire