Dual_Units_ShelbyYour Shelby GT500 will have no problem with fuel injection once you install JMS‘ PowerMAX FuelMAX Fuel Pump Voltage Booster. Expand fuel delivery by up to 80% and see how much better your muscle car performs. Make fuel pressure spikes a thing of the past with this PowerMAX FuelMAX.

Official Release:

JMS Chip & Performance has been revolutionizing fuel injection on Ford vehicles for years, and recently released new upgraded components. The JMS PowerMAX FuelMAX Fuel Pump Voltage Booster is now designed to be plug and play for 2011-2014 Shelby GT500 Mustangs, creating a simple and complete solution, with as much as an 80% increase in fuel delivery.

The JMS PowerMAX FuelMAX is the only voltage boosting product on the market that provides increased regulated voltage without noise, with every OEM and high-performance fuel pump application supported. This easy to use in-line device combines the better of two worlds in one product by offering both the highest maximum continuous voltage, and amperage available. The device has an uninterrupted output rating of 21 amps at 18 or 21 volts, and will operate with an input voltage between 9.5 and 19 volts DC with the lowest voltage drop on the market at 0.05 volts.

PowerMAX FuelMAX has user selectable maximum voltage ranges of 18 or 21 volts and output voltage is controlled by a simple control knob that adjusts up to 21 volts. You can also control the voltage ramp-in and ramp-out rate to correct or eliminate fuel pressure spikes to maximize performance and fuel delivery. There’s also a voltage save feature that allows you to save the output setting during the tuning process so the control knob can also be disconnected, and your voltage setting cannot be modified.

JMS FuelMAX Fuel Pump Voltage Booster for 2011-2014 Shelby GT500 comes complete with everything you need for simple plug and play installation. The system is designed to install in the rear cargo area and the wiring harness for the control knob is long enough to mount in the driver area. Just un-plug the OEM connectors and re-plug PowerMAX in-line at the Fuel Pump Driver Module and connect the ground using the factory hardware. This product is a first of its kind in the market and by far the easiest pre-engineered solution available for increased fuel delivery.


  • Expands fuel delivery by up to 80%
  • Offers very high maximum continuous voltage and amperage
  • User-selected maximum voltage ranges of 18 or 21 volts