Is 9.7:1 compression on iron heads too much for 91 octane

AJ, you're running the numbers in the same way as I am, and getting the same range of results. I was figuring about a 270 advertised duration and a similar ICA. And putting in the cam at 109-110 ICL and controlling the ignition timing as suggested will make this 318 a heckuva lot better all around than anything that can be done with the run-of-the-mill lower compression stock replacement 318 pistons.

OP is MIA, so this all may be moot.... and he still ought to balance the thing as these pistons are lighter than stock, by enough to put the bobweight well outside even the broad factory tolerance.