Inside Holley

Inside Holley’s New V3 Terminator X Software Update

Holley’s EFI systems have long been one the most popular EFI systems on the market. Today, however, the market is more diverse than it has ever been when it comes to aftermarket electronic fuel injection offerings. It is still a young market, as well, and EFI users continue to refine how they use the systems, better define their needs, and sometimes find that they need something that isn’t offered in their system. To meet these needs and to stay ahead of the competition, Holley has sought to add new advances to its products, and the latest V3 software update to Holley’s Terminator X EFI system is representative of that.

“The Terminator X is a little more street-oriented,” says Holley EFI software lead manager Ryan Witte. “You get a lot of guys that need decent racing controls, but not a Dominator-level of performance.”

This is the third version of software for the Terminator X EFI system, and previous versions will be able to update to this more capable edition. Witte noted that while Holley’s primary initiative with the update had to do with late-model engine support, the majority of the updates in this revision were consumer driven and suggested by the end-users of Terminator X systems.

“The Terminator X system is a decently featured system that is good for your average sportsman racer,” Witte said. “We are adding a fair bit of stuff that will make it even nicer for those racers.”

Expansion of Transmission Controls

One of the key updates is in the transmission functions, where Holley has added a “Racing Transmission” type that offers pre-defined features to control air shifters and/or dump valves. According to Witte, this is a pared down version of the same function that is available in the Holley Dominator ECU. In the Terminator X, users can control shifting up to eight speeds, two spool assist valves, and one large dump valve. If you need something beyond that, or support for a racing lock-up torque converter or Lenco/Liberty-style transmission, then you’ll need to step up to the Dominator.

In the Terminator X software, users can control shifting up to eight speeds, two spool assist valves, and one large “dump” valve.

“Probably the coolest thing on the street side is the integrated six-speed support,” noted Witte. While the Terminator X continues coverage of all of the GM 4L-based transmissions, Holley has worked out control for the 6L80 and 6L90 transmissions, as well.

“The GM six-speed automatics have an internal controller, and we’ve been trying to work with that to get the users good tunability. With the 6L80, there is another controller that decides when to shift. We will be able to include a Superchips F5 hand-held transmission tuner to directly reprogram it, simulating the stock vehicle with the Terminator X to keep the transmission content like it is running from the factory. The handheld handles shift points as well as  shift feel, speed, and timing,” Witte explained.

Other updates to the transmission functions in the Terminator X include support for TREMEC manual transmissions where the ECU will provide the transmission with speedometer data and operate the reverse lockout feature. This works with TREMEC T-56 and TKX transmissions.

New Boost Control Options

Turbocharger use is at an all-time high, be it from the OEM’s or in aftermarket performance applications, so boost control is often a hot topic when it comes to EFI tuning. Holley decided it was time to add two new boost control methods: Open Loop Duty Cycle mode, and Boost vs. Dome Pressure, to the Terminator X.

A lot of street performance applications want to save an input and/or output, meaning they don’t want to run a second solenoid or a dome pressure sensor. Historically, a dome pressure sensor was required, but now you just use one output and tell it what to do. This is a newly added item to the dropdown called Open Loop Duty Cycle.

“Open Loop Duty Cycle is a very basic way to do it, but we had a lot of requests for it. We really underestimated how many people would want to use it, but it is the cheapest way to hook up boost control,” Witte explains.

Boost vs. Dome Pressure mode is the other boost control mode that Holley added. Previously, there was a boost safety that that would shut things down completely when boost hit a user-programmed number. Now, with the new Boost vs Dome mode, there is a less heavy-handed measure. With the Boost vs. Dome pressure control mode, Holley added a maximum boost table in addition to the normal target dome pressure table mode above it. It’s a 1×16 table in the software that lines up with the target dome pressure table. It makes things easy in that you can use it to ride a target boost line. Witte says this works great on everything short of a Pro Mod car. If you’re guessing at your tuneup the first time, this buys you a little leeway.

Traction Control

New to the Terminator X is a reconfigured traction control ICF, or individual configuration file.

“The ICF is just one slice of a tune that you can load individually. You can do typical time-based control, a driveshaft and crankshaft curve, or wheel slip front versus rear,” Witte said. “These traction control features are new for Holley and allow the user to reduce boost, timing, nitrous percentage, or throttle angle (drive-by-wire) rate limit, so you can change how fast it reduces and how fast it puts it back in. It will also activate a rev limit for slip, as well.”

Holley, traction control, terminator x, holley efi

Terminator X received a new traction control configuration file that allows users to manage traction control through a number of variables, including timing retard and cylinder cut, as seen here.

The Holley EFI software in the Dominator also works with the Davis Technologies Profiler, TCII, and TCIII, and Holley has now brought that functionality to the Terminator X.

Late-Model Engine Support

With crate engines ever so popular and the latest OEM powerplants utilizing things like drive-by-wire and direct injection, Holley decided it was time to support these platforms and imbue its Terminator EFI system with features required by these more technologically advanced engines. To that end, there is now pulse width modulation support, among many other things.

“A lot of what drove the start of this update was improvements to direct-injection strategy,” Witte noted. “We wanted to create a plug-and-play solution for the LT.” In addition to the LT engine family, the software update also supports Ford’s 7.3-liter Godzilla engine platform.

“We now offer full VVT (variable valve timing) and electronic variable oil pump support,” Witte explains. “The LT and Godzilla have multi-stage oil pumps that can change the volume and pressure.”

Staging Output Control — Get The Bump But Only When You Want It

Many sportsman racers use a “bump” feature where the EFI controls the transbrake button and allows them to stage the car at the starting line by subtly bumping the car into the timing system beams. Holley added an advanced enable criteria at their customers’ request to be able to turn it off at a certain vehicle speed.

Holley, traction control, terminator x, holley efi

“A lot of people are worried they will bump the transbrake button, and this prevents that from happening by disabling the button at a set speed,” Witte said. “We give the people what they want.” While many drag racers may not be concerned with this, the growing number of drag-and-drive vehicles that both utilize the bump feature on track and see a lot of street miles can benefit from such a simple, yet perhaps important, update.

Datalogging Improvements

Witte noted that he is very much a “keep it simple” person, but the team felt there were improvements to be made to the datalogging section of the software.

Holley, traction control, terminator x, holley efi

“We added some new drop-downs and cleaned up the logger,” he said. “We made it remember a few more things which streamlines the experience, so the next time you open the log it’s closer to where you left off.” Other improvements include being able to search for specific channels while in the data monitor and graph file screens, hiding unused channels, and sorting the channel list alphabetically among many others.

Revisions To The Software Update Process

“Updating to a new version has always been a source of friction, so we made it a point to streamline that process, take the pain out, and make it easier to fix customer issues when they call with them during that process,” Witte told us. “Going from version 1 to version 2 can be painful. A lot of people would misstep and lose their tune, but with the newest version, you can download any tune out of the ECU and update it. It’s been a long-needed change and it’s here — it’ll make things very nice.”

Improvements To Diagnostics

As with any electrical system, it helps to have a capable diagnostic system to help you pinpoint any issues that may arise. To aid in diagnosing issues, Holley has implemented a new pin map, or output test mode.

“This output test mode is a brand new thing for us. We will be able to turn on any output to test it. If you’ve just wired up your new vehicle, you can test pins and hear solenoid clicks, or use a test light to verify the signal. You check wiring and devices without having to get creative to get the ECU to turn them on.” Witte said that the Terminator X is the first product to get this new diagnostic update and that it will be going to the Dominator and HP systems, as well.

We’ve only touched on a small number of the changes in this 3.0 software update for the Holley Terminator X system, but the engineering team has worked to update and upgrade the software to improve the user experience and offer additional options that the market has demanded.

Terminator X V3 Overview

The new release expands hardware support and adds a variety of popular software options:
Hardware Support:
– 6L80/90E Transmission Control (PN 558-499)
– 7.3 Godzilla Crank Sensor Module (PN 558-474)
– LT4 New Main Engine Harness (PN 558-130)
– T56 and TKX/TKO Manual Transmission
Software Updates:
– Pin Map Test Mode
– Traction Control ICF
– Boost Control Updates
– Racing Engine Type
– Datalogger Updates

– Expanded LT Engine Coverage

A complete list of all software revisions can be accessed HERE.

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About the author

Steve Baur

A lifelong automotive enthusiast, Steve Baur attended the University of South Florida for journalism and has worked as a technical editor and editor for numerous automotive publications for over 20 years.
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