I just use 93 octane with Klotz oil at 32:1. It still smokes, but hell I'm not racing so I'd rather be safe than sorry. I debated thinning her out a lil more but I'm not sure if it's a wise choice since my plugs are looking fine and don't foul often.
My friend's
white and red banshee in my pics has a cool head with 18cc domes. We use Klotz 110 octane fuel and 93 octane mixed together with Torco synthetic oil. I can't remember how much the ratio of 110 to 93 is, but it works really well.