SKU: 47724201336

HP EFI Universal MPI Retrofit Kits - 550-501

Sale price$2249.97 Regular price$2499.97
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Ships within 48 hours · Estimated delivery Aug 26 - Aug 31

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Description

HP EFI Universal MPI Retrofit Kits - 550-501Overview: Do you have a Mopar, Ford or other type engine you want to install multi port fuel injection on? No, problem, the Holley HP universal MPI retrofit EFI kits are designed to be used with any V 8 intake manifold. The kit comes with injector bungs and un machined fuel rails so you can modify to fit any single plane 4bbl intake manifold. The HP universal retrofit kits also come with the necessary wiring, ECU, sensors and throttle body. Just

Overview:

Do you have a Mopar, Ford or other type engine you want to install multi-port fuel injection on? No, problem, the Holley HP universal MPI retrofit EFI kits are designed to be used with any V-8 intake manifold. The kit comes with injector bungs and un-machined fuel rails so you can modify to fit any single plane 4bbl intake manifold. The HP universal retrofit kits also come with the necessary wiring, ECU, sensors and throttle body. Just select the fuel pump and injectors of choice and you are off and running.

Features:

  • NEW V2 SOFTWARE FEATURES
  • “Quick Start” ignition and fueling strategy for LS x Engines
  • Data Logger. Scalable axes, Smoothing, Multiple graph view ability, Pre-defined notes fields and many more
  • Strip Chart Real-Time Data Viewer
  • Integrated Boost Control - Boost vs Time, Boost vs Gear (Time or RPM), Boost vs RPM, Boost vs Speed, Launch control. Boost launch builder, Over-boost safeties, Boost scramble
  • Traction Control - Power reduction via timing, nitrous percentage or boost (Requires Davis Technologies Holley Module)
  • “Quick Start” fueling for all engines
  • Option for VE based fueling strategy
  • Fuel Map and Learn Function Smoothing
  • Configurable User Password Protection
  • Fully Configurable lap top Gauge Panel
  • FEATURES
  • Optional 5.7” full-color touchscreen LCD allows easy on-the-fly tuning,data-logging or can be used as an easy to see graphical gauge panel
  • Eight sequentially driven 8:2 peak and hold injector drivers, capable of driving up to 16 low or high impedance injectors as a standard feature. Multiple staged injector strategies
  • Eight channel Distributorless Ignition (DIS)outputs capable of directly driving “Smart” ignition coils or Holley DIS coils. Will drive 2 wire coils with the addition of PN 554-112 high current coil driver module
  • Plug and Play control of factory GM 24x and 58x LSx engines
  • Integrated single channel wide band oxygen sensor control. Works with NTK or Bosch sensors
  • Internal data-logging standard with a huge 2GB of memory
  • 4 Stage progressive nitrous control
  • Turbo boost control
  • Integrated water/methanol injection control
  • Self-tuning fuel table strategy greatly simplifies tuning process
  • Individual cylinder fuel and spark control allows you to unlock your engine’s potential
  • Works with 4, 6, 8 cylinder engines
  • Unique lb/hr based fueling strategy greatly simplifies and commonizes tuning
  • Advanced idle, closed loop, and enrichment strategies allow for very stable operation
  • ECU is fully potted and can be mounted in the engine compartment or interior
  • Sealed automotive and marine grade connectors
  • Allows for use of common OEM sensors as well as customer sensor calibration input
  • Ignition Plug and Play with GM 24x and 58x LSx engines, GM HEI, Ford TFI, magnetic and hall effect trigger, and other ignition systems. New Plug and Play applications in process. Custom settings can be configured to allow many other applications
  • 1-5 Bar MAP sensor capability
  • Two channel knock control sensor Inputs for both one or two wire knock sensors
  • Dedicated fuel and oil pressure inputs
  • Controls both stepper and PWM Idle Air Control (IAC) motors
  • Speed density, Alpha-N, or combination fueling strategies
  • 4 Programmable high or low Pulse Width Modulated (PWM) outputs and 4 fully configurable inputs can be configured for use
  • 4 Stage nitrous oxide control
  • Fully featured nitrous control eliminates the need for a separate nitrous controller device
  • Can be configured “Wet” or “Dry” with closed loop feedback
  • Progressive control based on time, RPM, or boost, requires part # 554-111
  • Lean or rich safety cutoff
  • Full timing retard/control configurability per stage based on RPM or time
  • Integrated Water/Methanol injection control
  • Uses Holley Water/Meth solenoids specially designed and calibrated for use with this EFI system to allow the user to enter Water/Meth flow as a percentage of fuel injector flow for Water/Meth tu

Application:

Year Make Model Submodel Engine Size
Universal

Specs:

Brand Holley EFI
Emission Code 3
Product Type Universal Multi Port
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 47724201336

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Andrea S.
Bozeman, US
★★★★★ 5
Great for night time play!
Size: One-Size-for-Most
This ball is great! It is a 2-for-one light up feature so we love the flashing lights and if she drops it in the snow after those lights stop, we can still find it because of the strong glow that gets its charge from the flashing LED lights. Our first one lasted a few years, we lost it on a trip so now back for our second one so we can keep the night time fetch going! She is a golden retriever for size reference. Any bigger of a breed and I would worry it might be too small for her mouth. It’s a bit smaller than a tennis ball. Just don’t make the same mistake I did and let them have it in the house at night, she walked up to my bedside while I was asleep one night and squeezed it to activate it. Those lights are so bright it was a rude awakening!
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Reviewed in the United States on November 11, 2025
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Katie
New York, US
★★★★★ 4
Good option for playing at night
Size: One-Size-for-Most
This ball is a good option if your dog likes to fetch at night. It stays lit for about 20 minutes or so, but that is me only leaving it out of the counter, being "charged" by whatever house lights are on. My dog isn't a big chewer, but it seems as though it would hold up well. I like that it is easy to rinse and clean. It seems to be a good value.
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Reviewed in the United States on January 16, 2026
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Amazon Customer
Port Orchard, US
★★★★★ 5
Night play
Size: One-Size-for-Most
My dog like many other dogs loves to play. We needed a ball that fit into the handheld thrower we had but something that we could find it at night. This has been wonderful!
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Reviewed in the United States on April 26, 2026
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Jordan
Los Angeles, US
★★★★★ 1
It stopped working after three play sessions
Size: One-Size-for-Most
I thought this ball was great until a week later it stopped blinking and got lost in the snow. We only played with it for three days for 20 minutes at a time. It should’ve lasted a lot longer.
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Reviewed in the United States on December 12, 2025
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Amazon Customer
Chelsea, US
★★★★★ 5
It’s absolutely perfect for fetch in the dark!
Size: One-Size-for-Most
We needed to find a glow in the dark ball to run our over active dog after dark ( gets dark now about 5 pm ish) I was hesitant to buy this ball at first. We went to try it out and it totally blew my expectations! The ball really glows, it’s a durable rubber and when it hits the ground it lights up blue and red. Incredibly satisfied and just ordered 2 more. If you need to run your dog in the dark, this is absolutely for you. Highly recommend it
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Reviewed in the United States on December 5, 2025

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