EEHack is a popular free program designed to do interesting things with the datastream of your 1994-1995 GM LT1 engine. It’s intended both for beginners and advanced users, and focuses mainly on tuning but is also invaluable for diagnosis.
It has undergone many versions and years of development with community input, and contains modules that allow you to temporarily control some engine parameters in real-time, perform advanced datalogging tasks and analysis to make good tuning decisions.
It used to have the first free flash tool for LT1 engines however I have developed a new tool called flashhack that does a better job (also free).
With EEHack, flashhack, and the EEX definition with tunerpro, you can have a very advanced and complete set of tuning utilities for your LT1 for nothing.