timing on 2002 gt

[Illini]

Hey guys I guess I'm a newbie to fords so I'll get that out of the way now. So far I've installed steeda underdrives,< steeda timing adjuster( today)>, C&L maf, triax w/ hurst t grip, MM strut tower brace and Yokohama 255/45/17. The problem is that I've read everybodies setting on their timing setting, and it's around 14-15. I tried it at 14 and got an intermittent ses light that resett itself. I backed her down to 13 and got a solid ses light, resetthe computer and it's at 12 with no problems. I'm running shell 93 octane in it. I didn't hear any det. 0n 14 degrees and made5 or6 luanches at 3000 rpm, ran first to 5800, and 2nd to 4000 something and let out, never any sound of detonation. And on my way to on14 degrees it started flashing ses. See theres a short strip of asphalt in front of my house that I launched on, but between that and the highway there's 2/3 of a mile on gravel. I drive like 10mph or less on it ,but could the dust from gravel road have temporarily blocked the sensor causing the ses light? Any thoughts or suggestions. I built my 436 hp malibu so I'm not a total idiot, but lack any experience with these mod motors.
P.S. The cars pulls stronger than before, even at 12 degrees