With your current pistons you will be at 11.6-1, way too high for any pump gas. A flat top piston would put you at 10.25-1 and would be fine on pump gas.
The Bowtie Phase 6 head is rather unspectacular in unported form,they are cast with small ports, it is intended to be ported heavily before use and only has flow numbers roughly comparable to a stock Vortec head if used unported. A cartridge roll blend helps, but it really takes full-on porting to make much of them.
Hope you didn't pay a bunch for them if they are not ported, virtually every aftermarket head is better out of the box.