Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 10 - Jul 15
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
Holley Terminator X MAX Engine Management Systems 550-918TERMINATOR X MAX MPFI W TRANS CONTROL Take control of your LS engine with Terminator X Max! Don't settle for a junkyard ECU with a cumbersome tuning interface when you can have complete control of your engine, self learning fuel strategies and the proven, race winning technology of Holley EFI at a budget friendly price! Terminator X Max features real time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable
TERMINATOR X MAX MPFI W/TRANS CONTROL
Take control of your LS engine with Terminator X Max! Don't settle for a junkyard ECU with a cumbersome tuning interface when you can have complete control of your engine, self-learning fuel strategies and the proven, race-winning technology of Holley EFI at a budget-friendly price! Terminator X Max features real-time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable inputs and outputs. The inputs and outputs are ideal for electric fans, boost control solenoids, progressive nitrous control, and much more. Part number 550-918 also has 4L60E or 4L80E Transmission control. Terminator X Max comes fully loaded with base maps for common LS engine combinations to get you out of the garage and on the road/track fast. The 3.5" touch screen LCD handheld contains an easy to use calibration wizard as well as tuning and gauge display functions. Also included is Holley EFI's industry-leading, easy to use software suite that allows full laptop access for advanced users. Whether you are building a budget beater or a boosted race car, Terminator X MAX has the features and technology you need at a price that won't break the bank!
Features:
- Designed for GM LS 4.8/5.3/6.0 LS Truck Engines and LS2/LS3 with 58x Crank, 4x Cam and 4L60E/4L80E transmissions, and EV6 Injectors
- Real-Time fuel map learn, takes the guess work out of tuning your base fuel table.
- High Impedance Injector Drivers will safely power most Stock LS injectors, and Holley EFI Injectors. Injector support chart provided in the instructions (Will not control Low Impedance Injectors)
- All of the new Terminator X Max systems utilize the Bosch LSU 4.9 wideband to relay AFR information to the ECU for accurate reading and precise tuning control.
- On-Board 1bar MAP sensor, is perfect for N/A or Nitrous engine combos. If your combination requires a 2+Bar, we recommend GM 12592525, and our adapter part number 558-416.
- MAP Sensor vacuum hose adapters (1/8th – ¼ and 3/16ths)
- 4 Inputs – 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, or activation triggers for nitrous activation, or a trans brake
- 4 Outputs – Ground, PWM - , for accessories such as; fans, boost control, nitrous control, IAC Kit, and More
- Boost Control – Boost vs Time, Boost vs Gear, Boost vs RPM, Boost vs Speed, Boost Safeties
- Nitrous Control – Single Channel of Wet or Dry, Progressive or Non-Progressive, Rich/Lean Safeties, and target Closed Loop AFR
- Advanced Tables – 4x 1D Tables, 1x 1D per Gear Table, 4x 2D Tables, 1x 2D per Gear Table, can be used for any custom tables you can dream up, such as Flex Fuel Sensor Offset Table, or a custom fuel or oil pressure safety!
- On-Board Diagnostic LEDS for: ECU Power – Engine Run – Wideband Status – TPS Calibration – Crank Signal –Cam Signal. Allow you to identify any Critical engine issues at a glance
- The included 3.5" Touchscreen Handheld contains a calibration wizard, that allows you to quickly build a base tune for any LS engine. Additionally the handheld provides internal data-logging and a fully customizable gauge display.
- The compact ECU size allows you to mount it virtually anywhere. Remember, diagnostic LEDS must face up!
- Plug and play compatible with more Holley EFI accessories such as; analog style gauges, shift lights, various modules, and coming soon, 12.3" digital dash support!
- Free EFI Tuning Software for complete control of your Terminator X power plant
- Includes: 58x/4x LS Engine Main Harness - EV6 Injector Harness - 4L60E/4L80E Transmission Control Harness - Terminator X MAX ECU - ECU Main Power Harness - Bosch LSU 4.9 Wideband Oxygen Sensor - Input/Output Harness - and assorted vacuum adapters.
Specs
| Brand | Holley EFI |
|---|---|
| Crank Reluctor | 58x |
| Emission Code | 3 |
| Ignition Type | GM LS 58x |
| Injector Connector | USCAR (EV6) |
| Product Type | Terminator X Max LS MPFI |
| Terminator LS Options | Fuel, Spark, Transmission |
| Part Number | 550-918 |
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
4.2 ★★★★★
Based on 1928 reviews
Sort
Product Reviews
★★★★★ 4
Great for dementia patients
I ordered this for my 94 year old mother with dementia to “feed” her stuffed cat. She was trying to feed her cat real food because “he’s hungry”, so this was a great solution. Her cat didn’t starve and mother was happy.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on September 1, 2025
★★★★★ 5
Topic of conversation
She wanted a puppy her mother got her ass stuffed dog so I bought the accessories it took her a little bit to figure out where they come from but it makes free continuous family laugh
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 19, 2026
★★★★★ 5
Long lasting dog treat
Flavor Name: Bacon, Size: 1 Count (Pack of 1)
My dog absolutely loved this stuffed shin bone—it kept her occupied way longer than most treats, which is always a win. It’s a great option when you need something that will actually hold their attention.
What I Loved:
• Long-lasting chew compared to typical treats
• The stuffing inside keeps dogs interested and engaged
• Helps with boredom and keeps them busy
• Once finished, the bone can be reused with other fillings
One Small Con:
• It can get a little messy depending on how your dog chews, so it’s best to give it in an easy-to-clean area
Who It’s Best For:
Perfect for medium to strong chewers or dogs that need something to keep them occupied for a while.
Final Verdict:
This is a great value and a go-to for keeping dogs entertained. I’d definitely recommend it if you’re looking for a longer-lasting treat that your dog will actually stick with! 🐾
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 11, 2026
★★★★★ 5
🦴 The Ultimate Distraction: A Must-Have for Power Chewers!
Flavor Name: Bacon, Size: 1 Count (Pack of 1)
Finding a chew toy that can withstand my 70-pound "House Hippo" (an expert-level destructor) for more than ten minutes felt impossible, until we discovered these stuffed shin bones. These treats are an absolute game-changer for long-lasting entertainment, durability, and distraction.
Exceptional Durability and Value:
The bone itself is thick, natural, and surprisingly sturdy. Unlike processed chews that crumble or get demolished instantly, these last for days of chewing. The value is tremendous because they provide two phases of entertainment: first, the intense effort of licking out the filling, and second, the satisfying work of chewing the bone itself afterward.
Irresistible Appeal (Peanut Butter/Cheese Filling):
The filling is the secret weapon! My dog goes absolutely wild for the flavor. The filling is firmly packed inside, which means he has to spend a significant amount of time actively working to get every last bit. This intense focus buys me hours of peace and quiet, which is invaluable. On top of that, they offer good nutrition!
Less Mess, More Fun:
I appreciate that these bones are relatively neat. They don't leave greasy residue all over the carpet like some marrow bones, and the durable exterior means minimal splintering (though, as with any bone, supervision is required). They satisfy my dog's natural chewing instinct while promoting dental health by scraping against his teeth as he works the chew.
Final Verdict:
If you have an aggressive chewer who needs a serious, long-lasting treat that is both entertaining and structurally sound, look no further. These stuffed bones deliver on their promise and are now a staple in our dog treat rotation!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 4, 2025
★★★★★ 5
Still Going Strong Months Later
Flavor Name: Bacon, Size: 1 Count (Pack of 1)
These stuffed chew bones have been amazing for my dogs. Even months later, they’re still happily chewing on them, and that says a lot since they’re aggressive chewers. The bacon and cheese filling keeps them interested, and the bones themselves are durable enough to handle their chewing without falling apart.
After all this time, the chews are still holding up and my dogs love them every time. They keep my dogs busy, help with dental care, and are definitely worth having on hand for large dogs who love to chew. Durable, tasty, and long-lasting—can’t ask for more.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 10, 2026
recommand products
New Balance Mens Fresh Foam Roav Running Shoes
16.94
Wolf Heavy Duty 72-Inch Countertop Gas Griddle with 1-Inch Polished Steel Plate
3824.97
ASICS Womens GT-1000 12 Running Shoes
19.94
Wolf Achiever 24-Inch Gas Countertop Hot Plate with 2 Open and 2 Step-Up Burners
1680.97
USR2126 - Tarcze hamulcowe nacinane seria USR (Para) EBC Brakes VOLVO | XC60 (T5) | XC60 | XC60 (D4) | VOLVO | XC60
145.44