Heads issue
I compare the Edelbrock heads to a set of well preped/pocket ported heads. The same power can be had from the J heads in this manor.
So, if your J's allready have work done on them, finish work lays else where, not in the heads.
For a street bound iron headed engine, pump gas fails around/after 9.5-1. But this is dependent of a few other factors as well, but thats the general area.
Like Mr. Mopartech was saying, bigger cam which bleeds off compresion helps. Other ways of beating a "Too high" ratioed engine just simply rob power or require more work in coating pistons and polishing chambers with coatings. And theres no sense going that way.
Just refresh your heads at best.