73 Mustang, c6, 3.50 gears 4v closed chamber flat tops. I have total advance at 36 degrees. Weekend cruiser.
I always run premium, which here in AZ means 91 and I have added super 104 for as long as I can remember. I get a little pinging sometimes and can probably fix it by slowing the advance curve since I have a lot of initial timing.
But yesterday I was running low on gas amd didn't have any super 104 in the trunk (I usually carry a spare bottle). So I filled her up with 91 octane and figured I would just drive less agressivly on the way home. I really figured it would start to ping real easy. But the weird thing is, it seemed to not really ping at all. I even got on it a few times and couldn't hear the ping.
I will do some more experimenting today but I am curious as to what gas/octane boost combo you guys use, if any. Super 104 isn't cheap and I know that previous engine setups (2v open chamber) would ping like crazy without it.