HP EFI ECU

Holley HP EFI ECU, part number 554-113. The HP is Holley's mid-range standalone engine computer: plug-and-play on GM 24x and 58x LS engines, and configurable for most other 4, 6 and 8 cylinder engines. It handles fuel, spark, boost, nitrous and water-methanol in one potted, sealed unit you can mount under the hood or inside the car.

What's in the box: the HP ECU only. The main harness, injector harness, ignition adapter harness and wideband oxygen sensor are sold separately.

Fuel

• Eight sequential 8:2 peak-and-hold injector drivers, able to run up to 16 high or low impedance injectors with staged injection strategies
• Speed density, Alpha-N or blended fueling, with an optional VE-based strategy
• Self-tuning fuel table with map and learn smoothing
• Individual cylinder fuel and spark trim
• lb/hr based fueling that keeps tuning consistent from engine to engine
• Quick Start fueling for all engines, plus advanced idle, closed-loop and enrichment control
• Drives stepper and PWM idle air control motors

Ignition

• Eight-channel distributorless ignition outputs that drive smart coils or Holley DIS coils directly
• Runs two-wire coils with the optional 554-112 coil driver module
• Plug-and-play with GM 24x and 58x LS, GM HEI and Ford TFI; also supports magnetic and Hall-effect triggers and custom setups
• Two knock sensor channels for one or two wire sensors

Sensors and inputs

• Built-in single-channel wideband oxygen sensor control (NTK or Bosch)
• 1 to 5 bar MAP sensor support
• Dedicated fuel pressure and oil pressure inputs
• Four configurable inputs and four programmable high or low side PWM outputs
• Works with common OEM sensors or your own sensor calibrations

Power adders

• Boost control by time, gear, RPM or speed, with launch control, boost builder, over-boost safeties and boost scramble
• Four-stage progressive nitrous control, wet or dry, with closed-loop feedback, lean and rich cutoffs and per-stage timing retard (progressive control needs 554-111)
• Integrated water-methanol injection using Holley solenoids, with flow set as a percentage of injector flow
• Traction control through timing, nitrous or boost with the Davis Technologies Holley module

Data and tuning

• 2 GB of internal data logging
• Data logger with scalable axes, smoothing and multiple graph views
• Real-time strip chart and a configurable laptop gauge panel
• Optional 5.7-inch color touchscreen for on-the-fly tuning and gauges
• Password protection for your calibration

Hardware

• Fully potted, sealed automotive and marine grade connectors
• Mounts in the engine bay or interior
• Coast Guard approved

Emissions

This part is legal for sale and use on uncontrolled (non-emissions controlled) vehicles only: 1965 and older U.S. built California certified vehicles, 1967 and older U.S. built federally certified vehicles, and 1967 and older foreign built vehicles.