Sure, things were great 30 years ago when you could pick up a cool piece of Aussie muscle for a few grand, throw some performance parts at it and have some fun on the street or strip. But most of those cars really weren’t that quick by today’s standards, and the very few properly swift machines at the pointy end of the sport were crafted by legends achieving goals the rest of us could only dream about.

First published in the July 2024 issue of Street Machine

Fast-forward to today and average folk like you and me can build a very quick car these days, and that’s largely thanks to the advances in engine management systems.

So, when we went looking for some trick engine management for our latest build – a twin-turbo, 427ci VS Commodore ute named Grimace to take on Street Machine Drag Challenge – we looked no further than Haltech’s latest and greatest piece of high-tech wizardry, the Nexus R5.

The Haltech Nexus R5 doesn’t just have all the bells and whistles, it’s a whole orchestra ready to crank out tunes that will power your project into a new dimension of performance. It’s not just an engine management system, it’s a whole vehicle control unit (VCU) that can manage every aspect of your car’s engine, transmission and power distribution needs.

And you don’t have to pay extra to unlock all its special abilities. When you buy a Haltech Nexus in either R3 or R5 spec, it’s ready to go, with all features unlocked. If you’re running an LS, you can even order a pre-terminated loom for your R5, so you’ll be ready to party in no time.

That’s not to say there won’t be a little work involved in getting it all set up, but anyone with a general idea about how electrons travel across copper wires should be able to sort it out. Simply put, if you can wire up a relay, you can wire up a Haltech Nexus – at least enough to get the car to your chosen tuner so they can work their magic.

Read on to learn how we installed the Haltech Nexus R5 in our Drag Challenge ute.

STEP-BY-STEP:

1. The Haltech Nexus R5 (lower left) is a fine piece of automotive electronics that can meet all your vehicle control needs. However, Haltech also makes a range of accessories such as digital dashes, CAN keypads, sensors and expansion units, which can amplify your experience to the max. You can also add up to four PD16 power distribution modules (PDMs) for even more body control functionality.

2. Roughly 26cm long and 15cm wide, the Nexus R5 is powered via a pair of SurLok connectors that come in the box. On the lower side of the unit are five connection fields for your loom. Haltech offers a pre-terminated LS loom as well as a universal V8 loom.

3. We decided to pair our Nexus R5 installation with a Haltech iC-7 digital dash; the two can be connected via a CAN-bus cable. A 3D-printed Mako Motorsport insert to suit the iC-7 was also purchased for a clean, trouble-free, bolt-in solution.

4. It’s a good idea to read all the installation booklets that come with the ECU (and in our case, the pre-terminated loom) and map out a plan for your additional connections. Once you’ve finished the job, keep a copy in your car.

5. The Nexus R5 is a chunky unit, so finding a spot for it can be a challenge. We decided to mount ours on the firewall behind the glovebox, sacrificing the heater for now. We used the heater bolt holes to support the mount we’ve attached the Nexus to, along with the CAN hub and thermocouple amplifier.

6. The mounting position of the Nexus R5 was dictated by the length of the pre-terminated loom as much as anything. If you’re looking to mount the unit under the seat or elsewhere, we suggest building your own loom using a Haltech universal wiring kit.

7. Our 427ci LS uses a Proflow DBW (drive-by-wire) throttlebody, which required us to fit a suitable DBW pedal (GM part number 92238396). We designed a mounting plate in CAD (computer-aided design) and used MPW’s plasma table to cut it out, but custom mounts for DBW pedals can be found online to suit most popular models.

8. We recommend buying some quality crimpers from Haltech (part number HT-070300); these are critical to making decent connections in your ancillary looms. Haltech also sells a harness sleeve pack (part number HT-039300) that includes heat shrink, sheathing and cables ties, which will take your wiring to the next level.

9. As with any new product, read the damn manual! Every Haltech product comes with comprehensive written information in the packet. There’s also a wealth of info on the company’s website in the Haltech Support Centre, and if you really get stuck, you can always ring the help line. Haltech’s product support is second to none.

10. Many people use aftermarket coils these days for the best ignition, so if you’re going for maximum performance, plan on making your own coil loom. We designed a coil bracket in CAD to mount our Haltech IGN-1A coils, before making up a loom to suit.

11. The status lights on the front of the Nexus R5 will tell you straight away if you have a problem: green is good; red is not so good. In this photo, the red light is telling us that we don’t have the Wi-Fi functioning correctly – an easy fix.

12. Using a pre-terminated loom has its pros and cons. On the minus side, some leads are going to be too long, so you might have to hide some slack – it’s a one-size-fits-nobody situation. On the plus side, the loom will work straight out of the box with the extra functions already terminated and ready for hook-up. This was a massive advantage for me!

13. The combo in our VS ute is a 427ci Gen IV LS comprising a Dart block, Pulsar turbos, K1 crank and rods, Wiseco pistons, Crow Cams hydraulic-roller cam, Johnson lifters, and Proflow 276cc heads decked out with PAC springs, titanium retainers and good valves. All up, it should be good for somewhere between 1300 and 1500 horses.

14. You can easily modify and tune your base map using Haltech’s NSP software, which can also be used with the company’s old Elite-series ECUs. It can be daunting at first, but the search bar is your friend here; just search for what you want and give it the parameters you need. Still too much? There are literally hundreds of tuners who can help you.

15. Success! After installing our Nexus R5, we added the pre-terminated loom, connected it to the engine, wired in the IGN-1A coils, plugged in the data we needed to create a base map, and then fired it up. Need proof? Check out the fire up video here! And you can watch Grimace’s first 1000hp pull on the dyno here: