could I get a little more info on my 454 stuff?

[baclay9]

I tore down my 454 today, well it is actually a 468...

It has Speed Pro Hypereutectic Pistons. Part # H581CP They are dome top and have the place where the valves go.

I am putting a set of 781 casting heads on it and was wondering what kind of compression ratio I was going to have? Any help on this is appreciated.

Also the engine has been balanced. Someone told me today I need the harmonic balancer and flywheel that goes with that crank or it will tear my bearings up. Is that true? Are the flywheel and harmonic balancer balanced along with the crank? Because I don't have them.

If you need more info to give me an answer just let me know. Thanks