wot low power

Hello, I have been having persistent problems since before I replaced the lower intake(about 2 months ago) when flooring it in my turbo fox. The first drive out after replacing the intake I discovered my fuel pump was just hanging in the fuel tank, so I fixed that, and the car ran like a bat out...

1991 LX 5.0 automatic convertible. 100% stock top to bottom end to end. 50k miles on the engine, 250k on the transmission and body. No EEC codes. Runs well at idle, at cruise, at normal throttle opening (normal driving around town and on the highway). They only time I have a problem is at quick...