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Holley HP EFI ECU and Harness Kits 550-603

Holley HP EFI ECU and Harness Kits 550-603

550-603-CP

Regular price $2,849.95 USD
Regular price Sale price $2,849.95 USD
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HP ECU AND HARNESS LS2 & LS7
Looking for a plug and play kit for your GM LS engine? The HP ECU allows you to accurately control the fuel and ignition of your engine plus much more. Got a stock LS engine? Simply download a base map and you're on your way. Got a turbocharged, nitrous fed LS engine on water/meth? This HP EFI kit can control that too!

Features:

  • Simple Installation - Plug and Play control of GM LS2/LS3/LS7 engines. Just plug the harness into your factory sensors, wire the power and grounds and you are ready to take complete control of your LS engine
  • More Functionality - Provides significantly more functionality than OEM or other competitive ECUs (boost control, nitrous control, water/meth injection, plus a host of additional inputs and outputs to control fans, pumps, relays etc.)
  • Easy To Use - Laptop programmable ECU includes a variety of base maps that will have you hitting the cruise or track in no time
  • Ideal For Everything - including stock 5.3L engine swaps or all out, 3,000+ horsepower race cars that need a simple and powerful ECU and harness solution
  • Industry Leading Self Tuning Fuel Strategy - means less time tuning and more time enjoying the power of your LS vehicle
  • Kit includes ECU, harness, communication cable, software, USCAR (EV6 Style) injector connectors, and Bosch wideband O2 sensor, designed to be used with GM LS2/LS3/LS7 engines with factory GM coils and a 58 tooth crank sensor
  • ECU is fully potted and can be mounted in the engine compartment or interior
  • Sealed automotive and marine grade connectors
  • 1-5 Bar MAP sensor capability
  • Optional plug and play hand-held programmer, 5.7" touch screen and digital gauges are available for ultimate control and vehicle monitoring
  • ECU is certified to ISO 8846, SAE J1171 & United States Coast Guard Requirements for Ignition Protection & Fire Resistance
  • For a full list of advanced features such as boost, nitrous, water/meth, individual cylinder control and more click the document icon under the product image! 

Application

  • Universal

Specs

Brand Holley EFI
Crank Reluctor 58x
Emission Code 4
Ignition Type GM LS 58x
Injector Connector USCAR (EV6)
Product Type HP EFI Kit
Part Number 550-603
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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 (Car Part People) 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:
Car Part People
218 S Lyman St.
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 policy and page were last updated: July 14th 2023

FAQs

|Q. What is an Intermediate Brake Line?

|A. 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. 

|Q. What is included in a pre bent brake line kit?

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

|Q. I need to return something -  what's your return policy?

|A. 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. 

|Q. I live in the area. Can I come and pick up parts?

|A. 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.

|Q. Do you sell just one line from a kit? 

|A. Unfortunately we cannot offer single lines outside of kits

|Q. Do your parts have a guarantee?

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

|Q. Can I pay with a check, money order, or cash?

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

|Q. Can I have this item shipped to someone other than myself?

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

|Q. How long will it take for my order to arrive?

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

|Q. I need a part for my car that you don't have listed. Can I special order one

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

|Q. Will you ship the part to anywhere in the world?

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

|Q. How do I determine left or right of my vehicle?

|A. 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.

|Q. I just got my tracking number and there's no info!

|A. 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.

|Q. Do you ship to APO or FPO addresses?

|A. Yes! Thank you for your military service!

Still have a question or concern?  Please Contact Us!