Maximum advance curve on my 360

Well, you really need to know what the static compression is. But, there may be other things you can do, providing the timing mark is right. You have a low convertor, and a high rear gear. Those combine to try to pull the engine down in rpm, and as you have seen, that cam is ground to make cylinder pressure. I would pull a head, and cc the chamber. Detonation starts on the intake side of the cylinder in most cases. So if there is that normal "eyebrow" looking area around the intake valve seat, polishing that a little and smoothing the chamber would go a ways to helping. It would also give you the chance to figure (calcualte) your true compression. Use the 1" down method on the cylinder to account for the valve pockets, and cc the head. Depending on those results, you may want to swap cams, or retard that one you have. On the "easier" side of things, you can re-adjust your timing curve. All the books say "get it in as fast as possible". But you cant. So perhaps going to a heavier spring to delay the rpm that you reach full advance to about 3300 would help. In most cases, the later the spark on pump fuel, the better (more efficient) the burn will be, and the more pressure gets on the crank throw during each firing cycle. That's because the fuel burns so fast, it doesnt take long for the pressure to develop. If you develop peak pressure too early because of too much advance, you put stress on the lower end, push towards the detonation threshold, and waste power on pumping losses.