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- USA
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Ships within 48 hours · Estimated delivery Jul 8 - Jul 13
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Description
Holley HP EFI ECU and Harness Kits 550-602HP ECU AND HARNESS LS1 & LS6 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! Stop reflashing your factory ECU every time you make a performance modification. Get Holley EFI today!
HP ECU AND HARNESS LS1 & LS6Looking 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! Stop re–flashing your factory ECU every time you make a performance modification. Get Holley EFI today!
Features:
- Simple Installation - Plug and Play control of GM LS1/LS6 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 and and Bosch wideband 02 sensor designed to be used with GM LS1/LS6 engines with factory GM coils and a 24 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" touchscreen 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
-
Univesal
Specs
| Brand | Holley EFI |
|---|---|
| Crank Reluctor | 24x |
| Emission Code | 4 |
| Ignition Type | GM LS 24x |
| Injector Connector | Jetronic / Minitimer (Bosch) |
| Product Type | HP EFI Kit |
| Part Number | 550-602 |
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- 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
4.7 ★★★★★
Based on 955 reviews
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Product Reviews
★★★★★ 4
Good for Teething puppies
Color: Teething Stick
After getting my fingers chewed and bitten by my new foster - 8 week old Yorkie , I was desperate to find good teething toys. Fortunately this one arrived quickly. Turned out to be very good for teething puppies! Charlie loves this cooling stick. Once it’s frozen, the cold really seems to soothe his sore gums. The icy part doesn’t stay frozen for long, but it works so well that I bought a second one to keep ready in the freezer while he’s working on the first.
Even after it warmed up, he still enjoyed chewing on the soft stuffed part and the tentacles. The product card says not to use it as a chew toy, so supervision is a must, but it held up just fine so far.
Overall, this has been a big help during the teething phase — short-lived when frozen, but very effective while it lasts! And worth every penny to save my fingers from being a chew toy.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 7, 2025
★★★★★ 5
From Puppy Teething to Adult Favorite – 7 Years Later
Color: Teething Stick, Color: Teething Stick
This has been one of the best toys I’ve ever bought! My dog has loved the Pupstages Cool Teething Stick since she was a tiny puppy, and now at 7 years old, it’s still one of her absolute favorites. It’s been amazing for soothing teething when she was little, and now she still enjoys chewing on it and carrying it around.
It’s held up surprisingly well over the years, especially considering how much use it’s gotten. I also love that you can cool it for extra relief—it really helped during those puppy stages.
If you’re looking for a toy that lasts and actually becomes a long-term favorite, this is definitely it. Highly recommend for both puppies and even older dogs who still love a good chew! 🐶
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 1, 2026
★★★★★ 5
Great for little dogs that like to chew
Color: Hedgehog
Great for my 10 lb chihuahua that loves to chew! Keeps his teeth clean!
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Reviewed in the United States on June 7, 2026
★★★★★ 5
Cute Fun Puppies Love it Immediately Good Price
Color: Teething Stick
This little top was a huge success for my active Multipoo! She started playing with it immediately. I think it will become her favorite toy! It isn't expensive. It is well made and very cute!
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Reviewed in the United States on June 7, 2026
★★★★★ 4
My puppy loves it
Color: Teething Stick
It's cute and a good size for my chihuahua puppy. It seems to be slightly tearing at the seam in the middle, but hopefully it will hold up.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 16, 2026
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