Pay in installments of $343.74 with
,
and
Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 16 - Jul 21
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
HP EFI ECU & Harness Kits - 550-601Overview: 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
4.0 ★★★★★
Based on 27 reviews
Sort
Product Reviews
★★★★★ 5
Great dog balls at a great price
Size: Medium
The balls are a favorite for my dog. I could have done without the hole through the middle because I don't do treats in balls anyway. My dog loves balls for their own merit. I needed replacement balls for my Nerf Dog Ball launcher. It seems the originals have disappeared from the market. I took a chance because the price is right and this Chuck-it ball works very well so we're liking this ball a lot. So far my Dachsund, who can destroy a tennis ball (the kind they are selling as Nerf Dog replacements) in 3 minutes has not done any damage to this one so that's a win. I recommend this as a much better ball than the fuzzy tennis balls. I like the colors too since many dog toys are green (which gets lost in the lawn, etc.) or red (even though dogs have red/green color blindness. Blue and orange are good and pretty easy to find. I liked these well enough that this set was my second purchase so I will have spares in case the others are lost.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 21, 2023
★★★★★ 5
My Baby loves his new baby!
Size: Medium, Size: Medium
Finally! A ball my 107 lb. pitty/pointer mix can’t destroy. He has torn up every single “indestructible” toy in a day or so until now. He peels fabric and fur off non-rubber toys. He is a 4-legged shredder. I’ve added pictures of him for a size reference of my dog versus this product. I know I had wanted that when shopping for this item.
This ball is now his beloved “baby.” He goes absolutely insane looking for it, chewing it, chasing it, and even sleeping with it. He won’t rest unless he knows exactly where it is. It is his only toy, and he is good with that. After getting this home, I tried giving him other choices, but he won’t touch them.
I was worried that he would rip it apart by putting his teeth in the holes, but so far, not a scratch. It is soft enough to collapse just enough to keep it from cracking when his jaws crush it but not so soft that he can rip it to sheds. The holes are large enough to prevent a suction or vacuum effect on his tongue or mouth. For his size jaws, it is a perfect fit. Other dogs might have problems with suction or be able to get their teeth in those holes and rip it apart. Who knows?
The older version of the Chuckit squeaky ball was his favorite for the year and a half he had it, but the way they make them now, he peels off the orange triangle in hours flat, the squeaker falls out (choking hazard), and then he rips it apart.
I’m going to stock up on these. I can’t imagine how crazy he will be if they ever stop production or change the materials.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 9, 2019
★★★★★ 5
Perfect for my dog
Color: Blue Puppy, Size: Medium Size 2
My dog (16 lb) LOVES to whip her toys around and throw them in the air to chase after them. This is the perfect toy for her to play outside by herself. I would repurchase for her over and over again if needed!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 18, 2026
★★★★★ 5
Pup loves this!
Color: Blue Puppy, Size: Medium Size 2
My pup loves his soccer balls. These are very durable although if you have a dog that doesn't grasp the concept of using the loops/straps to carry it, teeth could puncture it. They are a good value for the money if your dog likes to chase the ball, I get the smaller size ball for my dog (medium dog). They come with a pump but if you have a bicycle pump or a battery operated pump, it will fill much faster. Ours stay outside and even in the winter, they hold up well, just need a bit more air occasionally to keep it pumped up.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 16, 2025
★★★★★ 5
Strong Toy
Color: Blue Puppy, Size: Medium Size 2
My dog loves this toy and lasted months. Just ordered a new one.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 13, 2026