High compression with aluminum heads and pump gas???????

And that takes us back to Dcr's.
With aluminum heads, I can/have run up to 9.2 Dcr on 87E10. That was with 11.2 Static cr.With no timing issues and no detonation.
Guys with Iron heads are reporting success with Dcrs in the range of 8 to 8.6, on 91 to 93.
Your results may vary.

I wonder if I couldnt run 12:1 with a bigger cam, say with an ICA of 75*. That would get me a Dcr of wait-for-it............... 8.6...... Thats do-able on 87E10/aluminum, and 93/on iron. Lets see With an ICA of 75*, what cam would that be? Hmmm. That would be in the neighborhood of 295*adv. A pretty big cam to be sure. Almost not streetable. Almost.

I really think its about time we stopped making blanket statements about Scr and fuel.
Let me rephrase that; I stopped thinking about Scr in every way except as a means of obtaining a Dcr number with a certain cam.Or if your build is stuck with a Scr number, work the calculator in reverse to obtain the ICA for the Dcr/fuel combo that is known to work.
But hey, if someone wants to limit their Scr to 10:1, and run 93............Its totally your choice.