APPLICATION: The PSI Holley harness is compatible with all 24x (Gen 3) & 58x (Gen 4) LS/Vortec engines, drive by cable or drive by wire throttles, w/ 4L60E (1996+), 4L80E (1993+), or non-electronic and manual transmission applications.
PARTS INCLUDED: Complete engine and transmission Harness, Instruction Manual
ADDITIONAL ITEMS REQUIRED: HOLLEY Terminator X or Terminator X MAX ECU
The PSI Conversion Holley harness was designed as an alternative to existing harnesses available through Holley; focusing on higher quality components with greater efficiency and a simplified installation process in mind. All PSI harnesses are built in the USA with SAE-1128 spec high temp cross-linked polyethylene TXL (Polyethylene Cross Linked) wire. Terminals and connectors meet or exceed OEM specifications from Delphi/Aptiv, Yazaki, Kostal etc. All harnesses are 100% quality tested using Dynalab or Cirrus harness testing equipment.
NOTE: Terminator X MAX is required for drive by wire throttle control and/or 4L60/4L80 transmission control.
The Terminator X ECU features real-time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable inputs and outputs. The inputs and outputs are ideal for electric fans, boost control solenoids, progressive nitrous control, and much more. Terminator X comes fully loaded with base maps for common LS engine combinations to get you out of the garage and on the road/track fast.
When to use a Holley ECU over a factory GM ECU?
- Holley computers are recommended for use in race car applications where tuning may be updated or changed frequently for different race applications or tracks as well as frequent drivetrain changes. The ease of datalogging with the Terminator X is an added bonus for customers looking to record their engines performance at a drag strip or road course. Basically, if YOU want to be the Tuner, this system is for you.
Does a Holley ECU require custom tuning?
- All Holley computers must be set up with the Holley setup wizard to base map the tune on your engine. This can be done on the 3.5in Holley LCD screen or on a laptop. This base map is a self learning/adjusting tune that will get your engine fired up and running, however a custom tune from a professional tuner is always recommended for built engine applications to optimize performance.
CONNECTIONS FOR:
- Fuse/Relay Box
- Fuel Pump Control (Relay included)
- IAC and TPS on DBC setups
- Throttle body and Pedal on DBW setups
- IAT Sensor
- Oil Pressure Sensor
- Wideband O2 Sensor
- MAP Sensor
- Engine Coolant Temp Sensor
- Alternator Control
- Crankshaft Position
- Camshaft Position
- Fuel Injectors
- Coil Packs
- Automatic or Manual Transmission control
- Knock Sensors
| Connections from the Harness You Will Need to Hookup:
- Fuel Pump (Required)
- Switched Ignition Power (Required)
- Constant Power (Starter 12v Stud)
|
Compatible with the Holley Terminator X ECU p/n 554-152 and Terminator X Max 554-153.
The PSI Harness is an upgrade for the following Terminator X Kits: 550-903, 550-904, 550-905, 550-909, 550-910, 550-916, 550-917, 550-918, 550-919, 550-920, 550-926, 550-927, 550-928, 550-929, 550-930, 550-931, 550-932, 550-933, 550-934, 550-935.
This harness is compatible with a 6L80e when paired with the Holley Transmission Controller Kit 558-499.
This harness is compatible with an 8HP70 when paired with the Turbolamik Controller Kit Kit-WC-CA or a MAXX ECU Mini Kit
The HAR-HOLLEY wiring harness is a simple, reliable solution for running an LS engine with a Holley ECU. Designed for clean installs and easy integration, it helps eliminate the complexity of factory wiring so you can focus on getting your project running.
Each harness is professionally assembled using high-quality materials and thoroughly tested to ensure dependable performance. The design keeps wiring organized and easy to route, making installation straightforward for builders of all experience levels.
Whether you’re finishing a project car, upgrading your engine management, or building a custom performance setup, the HAR-HOLLEY harness provides a clean and dependable wiring solution.
