SKU: 61766872710

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 5 - Aug 10

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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: 61766872710

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B. T.
Birmingham, US
★★★★★ 5
Satisfied with quality used with Epson ET-8550. Last ship no box > slightly damaged corners.
Size: 11"X17"
I have had good results with the Epson ET-8550. So far I've used about 400 pages printing at the max quality settings. Now whether it is the ink or the ink in conjunction with the paper, but the prints once dry don't immediately run when splashed with water. Now I'll spray UV clear on most prints but I've been pleased with that aspect. Decent weight, good surface. The only kicker is that earlier orders arrived in boxes and those were well protected. My last order was in a just the poly bag, no box. If Koala cost cut the box, that's disappointing because many pages had their corners damaged despite delicate handle during shipping. (Har har) If you find you a corner that has been affected in shipping, what I do is feed the good end first and minimize the risk of an uneven corner causing jams. BT recommended
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Reviewed in the United States on December 17, 2025
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CJFLA
Louisville, US
★★★★★ 4
Good quality item
Size: 8.5"X11"
Good quality product at a good price.
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Reviewed in the United States on May 3, 2026
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Rare
San Leandro, US
★★★★★ 5
Thought my Paper was horrible!
Size: 11"X17"
beautiful glossy paper I purchased 110 paper from staples thinking this was going to be thinner when I received it was way thicker then staples paper was totally impressed very cardboard hard like paper, my only down fall is that I have the new inkjet printer from Brother and it never drys overtime I touch the print it comes off on my finger giving my pictures finger print's so I hav to send it back so a wonderful verified user text me and told me that I needed to change my printer to glossy setting again my printer is very new now my Koala glossy paper works amazing so its basically the best glossy paper I have ever seen and used. so I am giving this view my first 5 star rating that I have ever giving for me thats alot! Now I have to re order my paper 11x17 again lol....
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Reviewed in the United States on April 25, 2026
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Nathyn Brendan Masters
Omaha, US
★★★★★ 5
Great for Indy Comic and Zine Covers
Size: 11"X17"
I use both the 11x17 and 8.5x11 Koala Glossy Inkjet papers as cover stock for Night Phoenix Press mini comics and zines, most often as Kickstarter add-ons or promo items. For that role, they deliver. The gloss finish immediately gives even short-run projects a polished, professional look with the other side having a matte finish which I can flip over for sketch covers using the matte side for the exterior cover. Colors print vibrant, blacks are strong, and the surface takes ink evenly without streaking. The finish looks clean enough to pass for offset printing on both inkjet and laser printers. This paper is also great for comic covers because it can fold down the middle without splitting the gloss coating too much if at all. The 8.5x11.5 works just as well for minis, one-shot zines or inserts. Between the two sizes, I can cover nearly every indie project format I need. They have just enough weight to feel like a true cover while still running smoothly through an inkjet printer. These books are often handled by backers or used as handouts, so durability matters. The stock holds up, though glossy paper can pick up fingerprints or light scuffs if stacked loosely. Bagging finished copies or boxing them quickly solves that. For the cost, it’s a dependable option that makes Kickstarter rewards and promo zines look far more professional than plain paper covers. For creators producing indie comics, add-ons, or zines on a budget, this paper is one of the easiest ways to elevate presentation without driving up printing costs. -Nathyn Brendan Masters
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Reviewed in the United States on October 2, 2025
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Bernadette Israel
Lexington, US
★★★★★ 5
Ausurion products protection
Asurion is a great company to insure your products whenever you purchase items from online businesses like, Amazon. I had a portable hot spot device ordering from Amazon with a 3-year protection plan, unfortunately, the device has accidentally fallen and refused to turn on, then I went on Asurion Online website and filled in a claim and waited for approval to take that device for repair, luckily, they do not haven’t repaired shop services near me, they just refunded the original item price to me by Amazon Gift cards without knowing it few days than expected. I highly recommend Asurion for your product insurance needs.
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Reviewed in the United States on April 9, 2026

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