Hypertech Thermo Master Power Chips

Plug-In Performance for 1980's and 1990's GM Vehicles

The premiere name in classic automotive ECM programming, Hypertech became famous with this replaceable power chip, or "PROM", for older vehicles. Before the OBD-II port, OE computer chips on the ECM had to be physically replaced. Hypertech's Thermo Master Chip is one of the best PROMs available. It can create instant power by adjusting spark advance and air/fuel ratio.