Motosledneck 12, I believe your CR will be more in the range of 9.5-1. I am running a 69 3/4t chev 2x with a grandma 4psd, 4.10 dana rear. Have a .010 350 with flattops and 2 eyebrows valve cutouts. A 650 holley, 2 plane performer intake, set of those 190cc, 64cc Proform aluminum heads, Howards cam with 213* @.050 .430 lift. Put some long slot 1.6 stamped rockers on for a lift of .458 Have a Proform HEI with 12* initial and a total of 36* @ 2800rpm. Engine idles @ 650rpm with manifold vacuum at 15.5 inches. With the vac adv. to manif. vac. it runs at 53* total@ 3000rpm. I get no ping and run 87oct. pump gas. Engine is a little lazy below 1100rpm. If I up the intial to around 18* it pulls great off idle with no ping but my total goes to 60*. I am going to find a better adj. vac. can ( this can doesn't adj. it out properly) to bring the total down with vac adv. to 48* and set the initial to 16*. Obviously I have a little more tuning and adj. to timing management to do but the combo works very well. Also I feel a slight off idle, tip in, lean condition. I will be addressing this after I adj. the timing curve to what I need.
Your combo I believe will work fine....your just lacking in the heads flow. You will be fine, just watch your timing. Initial, mech. and total with vac. and make sure you don't run lean anywhere in the range you operate the engine.