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Holley HP EFI ECU and Harness Kits 550-606N

Holley HP EFI ECU and Harness Kits 550-606N

SKU: 550-606N
$2,685.95 USD
$2,685.95 USD
Sale Sold out

HP ECU AND HARNESS, FORD MPFI, NTK

Looking for a alternative for your stock or built late model factory FORD EFI engine? How about a replacement ECU for your older Holley C950? Holley has you covered. HP EFI ECU and harness kits are designed to be used with popular factory EFI engines as an alternative to the factory ECU and harness or as a replacement for your C950 ECU. The HP allows you to accurately control the fuel and ignition of your engine along with additional controls for nitrous, boost or water meth.

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
  • Includes NTK wideband oxygen sensor

Application

  • Universal

Specs

Brand Holley EFI
Emission Code 3
Ignition Type Coil - (No Timing Control)
  Ford TFI
  Holley Dual Sync Distributor
Injector Connector Jetronic / Minitimer (Bosch)
Product Type HP EFI Kit
Part Number 550-606N
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Policies and FAQs

Return Policy

We accept returns on products within 30 days of delivery. Return shipping is the responsibility of the buyer unless we, the seller, are at fault.

Fault reasons include but are not limited to:
  • Buyer was shipped the wrong product
  • Buyer was shipped a damaged product
  • The product page had incorrect fitment and the part does not fit the Buyer's vehicle
 
The Buyer will not be refunded outbound shipping unless the Seller (Modern Day Muffler & Brake) is at fault.
 
In cases where the Buyer purchases and ships the return please note that if the Shipper (ex. USPS, FedEx, UPS, etc.) loses the return we will not be able to offer a refund as the Buyer must contact the Shipper and make a claim.
 
All products must be returned in original condition, meaning that the product must not be damaged, installed, or missing pieces/parts. If the product is not in original condition a deduction will be issued of up to 50% of the purchase price of the product.
 
Opened boxes, plastic bags, and other packaging are not considered damage (excluding single use items such as, but not limited to, liquids, software, and other components that cannot be reused/resealed).
 
When we, the seller, are at fault, please Contact Us for a return label, products returned with a shipping label not provided by the seller will not be refunded to the buyer. Please also note that our return labels are issued with the dimensions and weight of the original shipment, if the product is being returned in any box/package besides the original please Contact Us with the dimensions and weight.

Returns must be sent to this address:
Modern Day Muffler & Brake
774 Broad Street
Wadsworth, OH 44281
 
Products returned directly to a manufacturer or the incorrect address may be issued a deduction or denied a refund entirely.
 
If a product was delivered outside the 30 day return window or is no longer in original condition please contact us as we may be able to issue a refund in store credit and/or with a deduction. If this is the case please Contact Us as these situations are handled on a case by case basis.
 
If there are any questions, concerns, or doubts about return eligibility please Contact Us and we would be more than happy to assist you.

This page and policy were last updated: July 14th 2023

FAQs

This is the line that runs from the front of the vehicle to the rear. On most vehicles it connects to a junction then you will have rear axle lines. On a few cars the intermediate lines will connect to the rear wheels. It is recommended to change the axle lines if you are replacing the intermediate lines.

Our kits include all of the solid metal lines for that section of the vehicle.

We are happy to help! Please help us to help you by going to our return form and filling out the form as best as you can in order to request a return.

  • Modern Day stands by our parts and is happy to accept returns within 30 days of purchase. Parts must be in new condition.
  • If a part arrives damaged, or is defective, Please report it to us immediately. So we can handle it for your promptly.

Yes but you will need to order in advance. All of our items are not stocked at our location. So please place your order online and we will notify you when it is ready for pick up.

Unfortunately we cannot offer single lines outside of kits

Yes, all are covered by the manufacturer's standard warranty. Most warranties cover the cost of parts. Any installation or other fees are non-refundable.

Online we accept PayPal and all major Credit Cards. If your are picking an item up we gladly accept cash.

We can only ship to your confirmed address in PayPal or your billing address if you pay with a credit card.

Orders typically Arrive within 3 to 10 days depending if it is a stocked item or something we have manufactured at time of sale.

Yes please send us a message through our custom orders page.

Yes, but items sent out of the continental U.S. may incur additional charges based on their destination

The left and right sides on a vehicle are determined as though you were sitting in the driver's seat. The left is the driver's side, and the right is the passenger's side.

Check it again tomorrow. It takes up to 1 day for the carrier to give status and a delivery date. UPS and FedEx provide delivery dates, USPS usually does not but they take no longer than 5 business days.

Yes! Thank you for your military service!

Still have a question or concern?  Please contact use our contact us form!

Yes! Thank you for your military service!

Warranty Information

Customer service is our top priority and because we value your time and energy we ask you to visit our Contact Us page and reach out so that we may assist you in finding the correct warranty for your product. Please include your name, the name on the order, the order number, and the SKU of the product to ensure the quickest and most accurate response to your inquiry.

Product Notices

*NOTE: Product images may not reflect actual product appeareance.