SKU: 43403171935

HP EFI Universal MPI Retrofit Kits - 550-500

Sale price$1777.47 Regular price$1974.97
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Description

HP EFI Universal MPI Retrofit Kits - 550-500Overview: 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 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

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 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
Ignition Type CD Ignition (No Timing Control)
Injector Connector Jetronic / Minitimer (Bosch)
Product Type Universal Multi Port
Terminator LS Options Fuel, Spark
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: 43403171935

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4.1 ★★★★★
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Rachel
Houston, US
★★★★★ 5
Super Sturdy with hours of fun.
Color: Wild Duck, Hare, Squirrel & Alligator, Size: Small
I got the small ones that you cannot put a water bottle in. These toys have held up way better than expected. I am dog sitting a very rough with toys dog named Chunk. He tears up ever. Single. Toy my dog (Ted) has. I bought new ones just for chunk. These appealed to me with the no stuffing, They were cheaper, and have a squeaker. Everything chunk needed. They arrived on time and I thought I wasted my money. They were super soft, like too soft. They felt flimsy and weak. Like 5 minutes with chunk and they be dead. 2 hours with my dog and they would have a rip. So far 2 of them (I set two out) have lasted the whole weekend. The bunny looks very rough and disgusting, but no rips, the squeakers still work, and no random fluff everywhere. I am going to wash the bunny once chunk leaves. My very careful doggo Ted loves them too. He throws them up in the air and catches them, plays tug of war with them, and no rips. They are super sturdy. He can’t wait until Chunk leaves (chunk is 2 and Ted is 12-13) so he can play with them.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 26, 2026
A
Verified Purchase
Amber B.
Fort Morgan, US
★★★★★ 5
Loved it
Color: Brown/Wild Duck, Size: Large, Color: Brown/Wild Duck, Size: Large
He loved it so much, he destroyed it so we ordered another. I didn't realize that you can stick an empty water bottle inside. Again, the first one didn't last long, but he enjoyed it
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 20, 2026
D
Verified Purchase
Doug Jones
Whiting, US
★★★★★ 5
Very fun interactive toy
Color: Brown/Wild Duck, Size: Medium
This toy is very versatile. There's no stuffing yet it's very soft so it can be used as a tug toy. It also makes for a fun fetch toy because it has a cavity to put a water bottle. It gives your dog something that crinkles and can be pierced when bitten and easily replaced with another empty bottle whenever necessary. That is what really makes this toy the standout of all the ones offered by Best Pet imo. I don't expect this to last forever but once my pup gets bigger we'll probably get the large size for her because there's not too many all in one fetch and tug toys at an affordable price.
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Reviewed in the United States on May 15, 2026
C
Verified Purchase
Cowey Crew
Fort Morgan, US
★★★★★ 4
Great Toy, but Big Dogs Destroy the Squeakers Fast
Color: Wild Duck, Hare, Squirrel & Alligator, Size: Large
My big dogs had the squeaker torn out in no time, but my little dog absolutely loves this toy. It’s the perfect size for her, and she carries it everywhere. Durable enough for small pups, just not tough enough for heavy chewers. Still a fun toy overall!
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Reviewed in the United States on February 15, 2026
L
Verified Purchase
Leigh Evans
Boise, US
★★★★★ 5
Fun for dogs
Color: Green/Alligator, Size: Small
Smaller than I expected, but the two little dogs love it! They love shaking it, making it squeak, tugging it against each other & chasing it when I throw it to fetch. They often sleep laying on it.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 25, 2026

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