My timing is advanced and every gas station has lowered to 91 octane from 92. Is this a problem or do i need to add an octane boost.
you could try it first, just to see if you hear anything… diff cars just respond differently for some reason…
I think I read some one on this board advancing their timing all the way with no problems (using premium gas)
Hell man, I advanced mine’s a little past 18 deg BTDC, running REGULAR fuel one time, and it still didn’t knock… didn’t hear no pinging noises either… 
depends on how far advanced you are. really, with the b18a you should be able to advance it pretty far and still be ok on premium, or even maybe 89 octane.
the compression in the b18a is so low to begin with that there isn’t as much to worry about.
J-Spec is running 87 on 18 degrees
I advanced mine all the way, and i’m running 87. no problems, but when i took my head off the stock valves were fried. They were white and had a powder glaze on them. O well, i have new stainless valves.