okay, so I don't have years of experience under the hood but ive been doing my own work and learning as I go.
I bought a 90 454ss truck all original bout a year ago. so far ive done.

4l80e tranny swap with harness, computer,vss buffer, instrument cluster, drive shaft all from a 93ss doner
headers/ straight duals w series 40 flowmasters/ pre heated 3 wire 02 sensor
complete over haul
edelbrock cam 2162
taylor 8.2mm spark plugs
180 thermostat
AFPR @13 psi with Holly high flow external fuel pump
stock injectors/tbi
stock intake and cast iron heads. ( plan on getting all aluminum top end later)
new water pump/timing chain....
3.73 gear ratio

anyway trucks a beast compared to how it ran....before mods.

i still felt like it needed to be tuned for better performance so I order chip from jet performance for a 93ss with 4l80e and 3.73 gears. when I installed it seemed like it helped but tranny would not shift gears. called jet performance and they said that the bammy on my computer was from an older vehicle and that it was not going to work?? so I shipped it back and now im looking for a different alternative.

any suggestions?