What higher octane does is make the gasoline burn for a longer period of time. If it's still burning when you're done with that part of the stroke, then it will want to shoot fire through the valves. Something like that.

The guy at Auto Zone told me that 'cause I was going to buy some octane booster. So it must be true. He said that it's meant for engines with bigger cylinders. Maybe more displacement.

 

Gasoline is made up of several different chemicals, primarily hexane, septane, and octane. Hexane and septane are what cause detonation ("knock"), and part of the refining process is removing them. The longer it's refined, the higher the percentage of octane present, and the higher the cost at the pump.

Any "octane boosters," such as lead, are non-gasoline additives which mask detonation. In theory this is good, but many of these additives cause damage to catalytic converters or other systems, not to mention raising emissions. AFAIK, the only safe octane-boosting additive is ethanol (max 10%).

There is nothing inherently bad about high-octane gasoline, but your S2k's is designed for 93/94 octane "premium" unleaded. Using anything higher or lower is a waste of money.