Hypertech TPI computer PROM chip. For L98 350. Auto trans but mine was a manual and it worked flawlessly. Had to get a custom chip when i went radical with the supercharger. Part number is: 128822.

from Summit Racing:
"Hypertech ThermoMaster Power Chips replace your stock PROM, which holds the settings for fuel flow and spark advance. This is a Stage 2 chip that optimizes the spark and fuel curves for max performance. The ThermoMaster Power Chip is designed for use with a 160 deg. thermostat and premium pump gas (91 Octane or better). Maximize the performance of your ride with a Hypertech ThermoMaster Power Chip!"

 

Still have this?

 

i never saw this reply! sorry! i reposted