Re: 347 compression HELP PLEASE!
Use the 58cc heads and keep the compression up.
Compression is your friend....it increases vacuum and aids in power and drivability.
Assuming 58 cc chamber,.038 gasket,5cc valve reliefs,and the piston at zero deck, you'll be in the 10.8-11:1 range. Now factor in the 70* abdc intake valve closing of the 282xe and you'll cranking compression around 175 psi. That should be fine on 89 octane,definitely safe on premium.
I don't think you'll make 500hp na,buy with the right head 450-470 should be doable.
11:1 347, Canfields, Bullet roller, Vic Jr, 750 Holley,1 5/8 Hookers,TKO,4.33