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 17 - Aug 22

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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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4.4 ★★★★★
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K. Ansley
Cuba, US
★★★★★ 5
Cozy & Comfortable
Fill Material: Down Alternative, Size: Queen/Standard Size
This pillow was a big surprise! Despite the size, it is so soft & comfortable. Being able to add & subtracting filling is wonderful. It's like having a custom pillow just for me. I am a stomach sleeper. I am able to cuddle the pillow & be very comfortable. Plus it recovers it's shape.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 5, 2026
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Jo Jo
New York, US
★★★★★ 4
Overall a great pillow
Fill Material: Down Alternative, Size: King Size, Fill Material: Down Alternative, Size: King Size
I slept on it last night and I do think I’ll like it. I was used to a memory foam pillow, son this will be a change. My reason for 4 stars is because the zipper barely opens and my husband and I tried everything short of ruining the pillow. In the end I had to stuff extra stuffing into a pretty small hole. Nothing seems wrong with the zipper but I saw another review said they couldn’t add more filling. If they fix that issue then I’d rate it 5. Yes it is soft but it doesn’t go flat and if you adjust and add some more under your head it doesn’t shift. I do recommend if you like a plush pillow.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 27, 2026
R
Verified Purchase
Rose Mueller
San Leandro, US
★★★★★ 5
Good Buy
Fill Material: Down Alternative, Size: Queen/Standard Size
Very well done and easy to use. I love being able to adjust the filling, and the ability to clean it.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 8, 2026
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NWGale
Charlottesville, US
★★★★★ 5
excellent medium consistency pillow
Fill Material: Down Alternative, Size: Queen/Standard Size
Pillow is medium firmness with extremely uniform compression consistency. i have a very particular desire for something not too hard or too soft and this is the sweet spot... more stuffing is provided so you can add (or remove) some if needed to get what you like...i didnt need to but liked to have that option. also the feel of the cover is nice.
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Reviewed in the United States on May 31, 2026
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Lisa427
Birmingham, US
★★★★★ 5
Immediately yes
Fill Material: Down Alternative, Size: King Size
I’m 50 and peri has been kicking my butt lately, so temperature management of my head (as that is the only thing effected by my hot flashes) has been an ever pressing project that I’ve been managing for the last 3-4 years. Hot sleeping has always been one of my curses, so adding perimenopause to the mix has been my own special hell. But Dyson fans, keeping the bedroom window cracked, and lots of all cotton gauze blankets have been imperative for me in the night. Pillows have always been pillowing, they just get warm and flipping them all night long is just finding the least hot version. I even keep 2 pillow choices on the bed while I sleep, and 2 more an arm’s length away on the chest at the bottom of the bed. Silk pillowcases are great for my hair and skin but they don’t keep cool. THESE PILLOWS, complete with the Beckham cooling pillowcases are chef's kiss. They feel like they’ve been in the fridge. Literally. Now do they stay that way, of course not. But they’re cool enough for me to fall asleep. And if I wake, I use the other side. And if I keep another on standby, I am literally finding the cool side of the pillow all night long. I’m not exaggerating either. These pillows are cool WITH the cooling pillowcases. You can’t use a pillow protector though, even if it’s cotton. It will ruin the effect. And you must use the cooling pillowcases. Do both, and you won’t be disappointed.
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Reviewed in the United States on March 9, 2026

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