I concur; I was running 28 psi on 91 octane pump gas on evo pink 560s and a rewired 255 in-tank. You should be JUST fine.
Doublecheck your sparkplugs, pull them and check to make sure you're not running lean or detonating. if you are detonating, you're more than likely experiencing preignition, and you should retard the timing accordingly.
Your gap should be between .28-.34, and you should be fine at 10lbs on the factory plug. You can try running a step colder plug, but be prepared for it to foul more quickly.
Hope that helps!
-Jake