If you have a project vehicle that has a Gen-3 or Gen-4 LS engine, or if you want to LS swap your vehicle with one of these engines, then the Haltech Nexus Rebel LS is here to make life easier while giving you complete control of your engine’s operation. Debuted at the SEMA Show in 2023, the Rebel LS standalone ECU aimed to help make it easier to LS swap the world.
To start, the Rebel LS ECU is not a repackaged product. Haltech designed it from the ground up specifically for controlling the Gen-3 and Gen-4 LS engines. To go along with the ECU module is a terminated wire harness to make it easier than ever to have your LS engine up and running. Haltech says the Rebel LS is not a plug-and-play system, and it’s not in terms of connecting to, or working with, factory control modules. However, the wire harness included in the box with the Rebel LS ECU comes ready to connect to your engine.
Haltech’s LS wire harness is a modular design that has a main trunk and from there, they include wiring breakouts specific to your generation of LS engine. You can connect a breakout for the cable-driven throttle body found on Gen-3 LS engines, or there’s a breakout for the drive-by-wire throttle bodies on Gen-4s. There are breakouts to use either EV1 or Ev6 fuel injectors, and breakouts for various alternators of your choice. For keeping tabs on the air-to-fuel ratio, Haltech includes a Bosch LSU 4.9 oxygen sensor and a weld-on bung for installing the sensor in your exhaust.
The Rebel LS kit comes with various sensors, including a Bosch O2 sensor and an air intake temperature sensor.
Additionally, the Rebel LS kit includes an air intake temperature sensor, and breakout wiring for a Gen-4 oil pressure sensor, MAP sensor, and the speed sensor found on T-56 manual transmissions. At this time the Rebel LS ECU does not control electronic automatic transmissions but that is something Haltech says is coming in a future update.
The beauty of Haltech’s modular breakout-style wiring harness is that it makes it easy to change components on your LS engine. If you have a cable-driven throttle body and want to switch to DBW it’s as simple as switching the breakouts that connect the main trunk of the harness to the throttle body. The same goes for the fuel injectors. You can switch from EV1 to EV6 injectors with a quick swap of the injector harness breakout.
As a standalone ECU, the Rebel LS differs from other Haltech ECUs in that the harness is already pinned, terminated, and labeled to correspond with the ECU configuration. This setup helps Haltech keep costs down while saving you a lot of time by not needing to pin out and configure inputs/outputs yourself. Additionally, there are configurable inputs/outputs to customize the Rebel LS to your liking. Included are five digital outputs, four digital inputs, two analog inputs, and one 25-amp output.
The Rebel LS ECU uses a CAN network to connect to, and work with, Haltech’s CAN accessories, including the iC-7 digital dash, the eight- and fifteen-button keypads, and the PD16 power distribution module (PDM). In fact, up to four Haltech PD16 PDMs can be connected to the Rebel LS to give you control over things like headlights, tail lights, and electric windows through the ECU’s software.
Because the Rebel LS was created from the ground up for LS engines, the software is tailored to get your LS running quickly and easily. Upon boot-up of the Rebel LS software, you will need to input some information to let the program know which components are being used and what the engine combination is so it can build a base tune file to get the engine running. This initial tune should get your engine started and from there, you only need to drive it. Haltech has equipped the Rebel LS with what it calls advanced long-term learning that gives the ECU the ability to continually make improvements to the engine’s tune. The longer the engine runs the better and more dialed in the tune will be.
From what we’ve seen so far, the Rebel LS ECU will have enthusiasts performing LS swaps easier than ever. We look forward to getting our hands on this standalone engine management system and bringing all of you a first-hand account of installing the Rebel LS ECU kit along with some dyno testing and real-world drivability feedback.