Dcr

I am currently building engine on the high side of DCR. This kind of stuff has always been interesting to me, so I wanted to build an engine like this.

My build is a 71 318 bored .030 over, with Icon 844 pistons, 302 heads, and a Comp XE284 cam. The machine work is not finished yet and so I don't have the exact specs, but it could be 9.75:1 SCR and 8.0 DCR. I have been considering 10:1 SCR and 8.2DCR... but I fear that is pushing past the limit on 91 octane on iron heads.

Maybe I should go for .035 quench and the 8.2? Does good chambers mean you can run 87 on 8.0 DCR and iron heads(Successfully)? Some people seem to think 8.5 DCR is max for 91 on iron(but nearing impossible) and 8.0 is more reasonable.

Another question, 87E10?(Not available in my area) 87 with 10% ethanol boost? Is it like 91 or better?