Low Power between 1500-3500 RPM

[Stallion2w]

I have a 90 LX that has low power response from 1500 to 3500 RPMs at WOT. 3500 on up she runs like a bat out of hell. The engine was freshened up 10,000 miles ago with new bearings, E303 cam,mild porting on the E7TE's, Typhoon intake ( Gasket matched),BBK 70 mm TB & Spacer, 73mm C&L mass air calibrated to the 19lb injectors, 160 degree T-stat, MAC Cold air induction kit, BBK adj. fuel reg set to 37psi, new MSD Blaster Coil, Mac 2.5" off-raod h-pipe, 2 chamber Flowmaster, stock headers, and 3.73 gears loaded into the rear. She has an AOD and runs great getting nearly 19 mpg as a daily driver but the power loss at the low end is driving me nuts...the spark plugs are clean and not showing any unusual burn patterns. I have not done any computer upgrades as of yet as I am unsure of what my best route to take on the chips as I still want to change heads and add a supercharger. Any ideas on how to straighten this out would be appreciated.