Ernie,
With the aluminum head stroker I can run this lousy 91 as long as I don't pull it hard but I still use the 110 Racing gas. With the big block and the steel heads it is harder to get away with this low octane stuff and I only use it when I am going far enough that I have to fill up. The aluminum lets you get away with a little more as it dissipates heat so well. So I normally run the 110 in both or mix it if I am going on a long trip. And no, I don't retard the timing unless I am out and have to use the low octane then I will retard it just enough that I can run down the freeway without pinging. I am thinking of putting wheels on my gas barell so I can tow it along behind the cars.
Ron
