Holden diagnostics

Holden diagnostics Mail order or dyno tuning and performance parts
ECU replacement and security relinking
Custom conv Specializing in Holdens from VR to VF.

Bench test simulation, ecu replacements and programming, diy scantools and upgrades, Ecu tuning and custom conversion programming.

Massive congrats to Damian, taking out Pro class in the Spuds trailer hire burnout comp last weekend! What a weapon! Alw...
21/05/2026

Massive congrats to Damian, taking out Pro class in the Spuds trailer hire burnout comp last weekend! What a weapon! Always driving at the top of the game and flying that HDL flag proud. Well done brother. Another one for the shelf! Peter Clarkson Bonnie Galloway Eddie Hart

🤘☺️🤘

10/05/2026

This gorgeous old EH was brought to us to iron out a few issues after being fitted with a Haltech Rebel LS ECU, alongside a Haltech PDM, 2x4 CAN Keypad and UC10 dash setup.

We went through and corrected a number of initial setup and calibration issues left behind from the original install, then got stuck into the tuning side of things. The end result was a massive improvement in drivability, with over 100Nm gained through a large portion of the RPM range, while completely eliminating the violent off-idle surge issue it arrived with.

We also configured the CAN keypad and drive-by-wire system to incorporate fully functional native-style cruise control, exactly how the customer wanted it.

Absolute credit to the owner and builders of this car — the quality of the build is easily a 10/10 on this girl 👌

punishthepad!!! 🤘Unfortunately we couldn’t make it to this one in person — but HDL was out there in force with 21 of our...
28/04/2026

punishthepad!!! 🤘

Unfortunately we couldn’t make it to this one in person — but HDL was out there in force with 21 of our customers competing… that’s 21 out of 65 entered cars! Massive turnout, and they absolutely delivered.

🔥 6 cars in the Top 10
🔥 HDL customers locked out the entire podium — 1st, 2nd, 3rd!

Couldn’t be prouder of everyone who showed up, drove hard, and represented us banners or not!

Huge congratulations to all our customers who made the event — and an extra massive shoutout to our podium finishers and trophy winners:

🏆 1st Overall — DARREN ROBERTS / LIMITR (11 years strong!)
🥈 2nd Overall — SHAUN JURY / BARELY
🥉 3rd Overall — DAMIAN HART / NUTTER

Category winners:
🏆 1st Female — SARAH HUMPHREY / ERROR
🏆 2nd Female — TONI WEBBER / MZBARA
🏆 3rd 6-Cyl N/A — DOUG GRIFFITHS / WEOUT
🏆 1st 6-Cyl Boost — SHAUN JURY / BARELY
🏆 1st 8-Cyl N/A — MIAH TARAWHITI / TINASS
🏆 3rd 8-Cyl N/A — BEAUDENE HURNDELL / WEONIT
👑 Tip-In King — TJ DORMAN (Feejoa) / SKRAPA

To everyone flying the HDL flag — thank you. The results speak for themselves.
Absolutely unreal effort from you all. Bring on the next one! 🤘🔥

26/04/2026

A couple of weeks ago, Shaun’s Barra-powered EA was dropped off to us to sort out a few issues. We quickly uncovered some wastegate and boost control problems, then reworked the original tune — all while dealing with an ECU platform we’d never previously tuned (thanks to Gav at HPR for giving us a crash course in how this system works!)

After a few burnout comps, we pulled the logs and dug deeper, uncovering heat-related tables activating on the pad that simply couldn’t be replicated on the dyno.

With just 3 days before Punish The Pad, we remotely jumped back in, reviewed the data, and made the final tune adjustments.

The result? The car was absolutely on point — helping Shaun secure 1st place in the Forced 6 Cylinder class and 2nd Overall!

Massive effort, mate — well deserved.

16/04/2026

Chris brought his manual VY HSV Clubsport in for a OTR and dyno tune. Asked for spark cut and decel flames 🔥 while he was here. 👍👍
Punching a easy 254rwkw peak

09/04/2026

This was a cool jobby!
Tony dropped off the mighty jacked AYEWW, fitted with Fitzroy Motorsports old stock car motor after the OG dropped a valve at the last round of 6 banger nats. Tasked with “just make it skid” a week before Rapanats Burnout Competition, we got to work on the AU ecu fitted with a J3 chip. Something we haven’t had a lot of experience in. Well… what a learning curve! But we got there in the end, making that rapanats deadline, Tony picked it back up on the way to the event but not before instructed to “test to see if it skids..”
After personally being at the event to watch the outcome, we were not disappointed! What a change that new engine setup made! To see him roll off the pad with a the biggest grin on his face made all the frustration of learning a new system worth it!
Can’t wait to see more of it in action!

Get into it team! Show us ya builds!!! 🛻🛻
28/01/2026

Get into it team! Show us ya builds!!! 🛻🛻

26/01/2026

This customer dropped their LS3-powered Ford F100 off to us with a list of drivability issues they wanted sorted.

The truck was running an aftermarket Link
ECU, so we started by diagnosing why it was behaving the way it was.
We found some vital missing sensors and configuration issues, so those were added and the ECU was correctly set up to suit the engine and combination.
From there, we retuned the truck on the dyno, then finished off with thorough road testing to make sure the improvements we saw on the dyno translated to real-world driving.

The result?
- Starts cleanly both cold and hot
- Idles smoothly with no clutch input
- No more intense bucking or surging
- No stalling when coming to a stop
- Throttle feel and response was greatly improved
- The fuelling model can now compensate for changes in air temp/density and doesn’t go lean.

At the end of the day, the customer is the one who has to live with the car.
You can make all the power in the world, but if it doesn't have basic manners, the enjoyment factor disappears fast.
We believe a car should be just as good to drive as it is to look at 👍

22/01/2026

Tony’s Austin on the Dyno with its new engine transplant. LS1, B12 cam, powerglide and high stall, this thing is ready to skid!
Being a high stall, power figures don’t reflect actual power to the ground due to the basic fundamentals of how a dyno measures it. But these combos will normally show around 280-300 rwkw in a tight stalled or manual setup. This one’s no different 👍👍

13/01/2026

Who doesn’t love a spark-cut limiter and some decel flames 🔥😜

These lads made the trip down from Auckland for a few touch-ups on their cam tune — and asked if we could add the spark-cut limiter and decel flames while we were at it 🔥

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