The guys above hit it right on the head. Have a look at the injector duty cycle if you are able to datalog. Also check out your fuel pressure drop across the injector. If its much lower than 39 psi, a fuel pump should be the first thing you buy. Since you are running an SCT tuner, you can add fuel across the board, assuming the FP can handle it. What size injectors are you running now? Any idea what power level you are at? I run the 47# injectors at 430 whp with room to spare. Do you lean out only at WOT? That could be an indicator that bigger injectors may be a good idea. If you are leaning out at partial throttle but not WOT, common sense tells you that your tune may need some attention.
Corsa Sport Axlebacks Megan springs: 1.5" front 2" rear drop, Hurst short shifter, Paxton NOVI 2200SL Centrifugal SC, CX Racing intercooler kit, Tial Q BOV, HPX MAF/ housing, Ford Racing 47 lb Injectors, GT500 Dual Fuel pump, BMR LCA, SCT X4 Tuner