Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 11 - Jul 16
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
HP EFI ECU & Harness Kits - 550-601NOverview: Looking for a plug and play alternative for your stock or built late model factory 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
Overview:
Looking for a plug and play alternative for your stock or built late model factory 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:
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 tuning precision unmatched in the industry
Application:
| Year | Make | Model | Submodel | Engine Size |
|---|---|---|---|---|
| Universal |
Specs:
| Brand | Holley EFI |
|---|---|
| Emission Code | 3 |
| Ignition Type | Coil - (No Timing Control) |
| Ignition Type | GM HEI Small Cap |
| Ignition Type | Holley Dual Sync Distributor |
| Injector Connector | Jetronic / Minitimer (Bosch) |
| Product Type | HP EFI Kit |
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 1197 reviews
Sort
Product Reviews
★★★★★ 4
Durable Chew Toy That Actually Holds Up to Strong Jaws
Style: Gorilla, Size: Large (Pack of 1)
This Hammer for Pets Super Treadz Gorilla Dental Chew Toy has been a reliable option for a heavy chewer, especially for a large breed with a strong bite. The material feels tough and well-made, and it stands up well to consistent chewing without immediately breaking down like softer toys tend to do. It also gives a bit of dental benefit by helping reduce plaque and tartar buildup during play, which is a nice bonus since brushing isn’t always realistic. The textured surface keeps it interesting enough to hold attention for a while, and it doesn’t splinter or create a mess. Overall, it’s a solid, durable chew toy that works well for strong chewers who tend to destroy most standard toys quickly.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 6, 2026
★★★★★ 5
Skye's Absolute Favorite Ball! 🐾
Size: 1 Pack, Style: Ball
Hello, I am Skye! I am an Australian Mountain Doodle puppy, and my humans finally found a ball that can keep up with me! The Benebone Natural Rubber Dog Ball is officially my prized possession.
Why I give it five paws:
The Perfect Chew: It is made of natural rubber, which means it has this amazing, springy texture that feels so good on my teeth. It's super tough, but it still has a satisfying squish when I chomp down on it.
Funky Bounces: Because of the rubber and the design, it doesn't just roll in a boring straight line. When it hits the floor, it bounces all over the place in crazy directions, which makes chasing it so exciting.
Easy to Carry: The texture makes it really easy for me to grab with my paws and hold onto in my mouth, even when it gets a little slobbery during a long game of fetch.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 24, 2026
★★★★★ 5
So far this is the perfect alternative to other wobble toy feeders. Please make a bigger size!
Size: 1 Pack, Style: Pawbler
Why did you pick this product vs others?:
I bought the Pawbler because the two most popular wobble treat feeders on the market are plastic, and one of my dogs just absolutely destroys those in no time because he bites them and throws them rather then nudging them and then he has plastic cutting him so I am forced to throw away a costly treat toy/dispenser. I thought maybe a rubber one would work out better. So far my dogs love it, it works well spitting out their kibble, seems to be holding up and is easy to clean and feels like a good weight, not a super flimsy toy.
I would love to see it made in a slightly larger size, I think this current size is good for medium dogs. It holds just under a cup of small round kibble but I would like to see one that can hold more and is slightly larger in size.
I have 4 german shorthaired pointers, my test subject for this toy is mostly my 70 pounder who bites the toys instead of nudging them and throws them across the room, so it is taking a beating. I think for him a larger size would be helpful in deterring that behavior but I also think this may be too small for larger breeds.
Durability:
So far this toy looks just like when I bought it. It has no punctures or scratches and unscrews without problem. We have only had it a week or so but we use puzzle/toy feeders to feed our dogs lunch every day so it is pretty easy to tell which toys won't last long. Obviously, I can't speak to long-term durability at the moment, but I can say that most toys similar to this end up already scratched or punctured in a few days, so this is already sturdier when compared to what I have tried before.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 26, 2025
★★★★★ 4
Well made and durable, not a toy the pups seek out
Size: 1 Pack, Style: Tug
Well made. Thought our staffies would love since they live tugging with each other. Sadly not something they seek out. We love ALL the benebone chews though!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 6, 2026
★★★★★ 5
Durable fun enrichment toy
Size: 1 Pack, Style: Pawbler
I had been wanting to buy one of these kinds of toys for some time but thought that the other brands I had seen were too pricey so this was a great compromise for the price. My 5 yr old Portuguese water dog loves it. He spent 25 min playing with it the first day. The trick is to find a treat that is just big enough where it doesn’t fall out right away so it makes it challenging and fun for them. He has been chewing on it a lot for a week and it has not broken or shown signs of damage. One thing to note is that there is a small hole on the bottom of the toy so you cannot freeze liquids in it without covering the hole in some way so that would be my only complaint. Besides that it’s a great toy that keeps him busy and happy.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on September 1, 2025