If you guys want to sit here and guess and err on the bad side...go ahead. Any moder past (about 10.3:1) should be running on no less that 100 octane. I have seen moders detonate and punch holes in 4 out of 8 pistons due to this detonation. My AS Mustang was right on that line and I spent the bucks and bought the fuel as 'insurance', cheaper than a new moder.
Good judgement is usually in hind sight, spend the extra dough on an 11:1 moder and run the good stuff.
