Up and go tuning

02/09/2026

02/09/2026

Let’s get that 12.7 !

01/09/2026

It’s like a solar eclipse ……….No, we didn't just hold a car meet for red Holdens only. In a quirky twist of fate, we currently have 6 red rockets in for maintenance and repairs. Only seemed fitting that we should line them up for a class photo.

🚗 Gen-F Maloo with DART 427 and Harrop 2650 blower.
🚗 VE SS Whipple Blown DART 427 7lt
🚗 HSV E1 GTS LSX Harrop HTV2300 Blown
🚗 VU Maloo Ute Head & Cam
🚗 VT Monaro Supercar Tribute 383 Stroker
🚗 VX Track Car Whipple Blown 427

01/09/2026

Another beautiful job by LSN WRAPS for all your wrapping needs please don’t hesitate to contact them for a quote

01/09/2026

WHY A CAMMED LS CAN HANG RPM

You lift off the throttle, push the clutch in and instead of the RPM dropping straight back to idle, the engine sits at 1,500–2,000 RPM before slowly coming down.

A lot of people blame the camshaft.

The cam is part of the reason, but there’s a lot more happening inside the ECU.

A cammed LS has different airflow characteristics at low RPM, particularly around idle and closed-throttle conditions. Increased overlap can allow exhaust gas back into the intake and reduce the stability of manifold pressure.

When you lift off the throttle, the ECU has to transition from a loaded operating condition into deceleration and eventually idle control.

This involves throttle position, RPM, MAP, calculated load, idle airflow, spark control and deceleration fuel strategies.

If the ECU is still supplying too much airflow while the throttle is closed, the engine has enough oxygen to keep RPM elevated.

But simply removing airflow isn’t always the answer.

The ECU also uses spark to control idle speed. If the calibration isn’t correctly matched to the camshaft, the combination of base airflow and spark correction can make the ECU fight itself.

You can end up with the throttle nearly closed while the engine is still receiving enough calculated airflow to maintain RPM.

Then you’ve got deceleration fuel cut.

The ECU has to decide when conditions are suitable to stop fuel delivery and when fuel needs to be restored as RPM approaches the idle region.

If those thresholds and transition strategies aren’t appropriate for the engine, you can get strange behaviour coming off the throttle.

A cammed engine can also produce very different MAP readings during deceleration compared with a stock engine.

That’s important because MAP and calculated load are involved in how the ECU determines what operating condition the engine is actually in.

This is why we don’t fix RPM hang by randomly changing one idle table.

We’re looking at the complete transition:

Throttle closes → airflow changes → MAP changes → calculated load changes → spark strategy changes → fuel strategy changes → RPM approaches idle.

If one part of that transition isn’t calibrated correctly, the engine can take too long to return to idle.

And this is where data logging becomes extremely useful.

We can see RPM, throttle position, MAP, commanded airflow, spark advance, injector pulse width, fuel cut status and other relevant parameters during the exact moment the RPM hangs.

That tells us whether the ECU is deliberately holding the engine up or whether the engine is receiving airflow it shouldn’t be.

A camshaft naturally changes the way the engine behaves.

The calibration needs to account for those changes.

A cammed LS shouldn’t need to hang at 2,000 RPM just because it’s cammed.

If it does, there’s a reason.

Find the reason in the data, then calibrate around it.

🇦🇺 UP & GO TUNING
Holden | GM | LS
Road & Remote Tuning Australia-Wide
HP Tuners | Custom ECU Calibration | Data Log Analysis

01/09/2026

HOW HEAT SOAK CHANGES ENGINE BEHAVIOUR

Heat soak is one of those things you can completely miss if you only look at a cold start or one short pull.

As the engine bay and intake system heat up, the conditions the ECU is working with change.

The IAT sensor becomes particularly important. As intake air temperature increases, air density decreases. For the same volume of air entering the engine, there is less oxygen mass available.

The ECU needs to account for that change.

On a MAF-based LS, the MAF is still measuring airflow, but IAT is also part of the ECU’s calculations and corrections. As temperatures rise, the ECU can alter fueling, spark and other strategies depending on the calibration.

Then there’s heat inside the engine itself.

Higher ECT can change spark corrections, idle behaviour, fan operation and other temperature-dependent strategies.

Heat can also affect the fuel system.

Fuel temperature, fuel pressure behaviour and injector operating conditions can change as everything under the bonnet gets hotter. If the fuel system is marginal, the problem may only become obvious after the car has been sitting in traffic or driven for an extended period.

This is why a car can feel completely different cold compared with fully heat soaked.

You might see:

Higher IAT.
Different MAP.
Different fuel trims.
Different spark correction.
More knock activity.
Changes in idle quality.
Different throttle response.
Changes in calculated airflow and load.

And that’s exactly why we don’t want to validate a calibration under one perfect set of conditions.

A tune that looks great during the first pull doesn’t necessarily tell us what happens after the engine bay has been heat soaked, the intake temperature has climbed and the vehicle has been driven through normal traffic.

When we’re looking at a heat-soaked vehicle, we’re comparing the data.

IAT vs airflow.
IAT vs spark.
ECT vs spark.
Fuel trims vs temperature.
Lambda vs temperature.
Knock re**rd vs temperature.
MAP and load vs temperature.

We’re looking for changes that make sense and changes that don’t.

If the engine becomes unhappy as temperatures rise, we need to determine whether the ECU is correctly compensating or whether we’re seeing an underlying mechanical, fuel-system or airflow problem.

Heat soak isn’t just:

“The intake got hot.”

It’s a change in the operating conditions the entire calibration is working around.

That’s why proper tuning needs to be validated cold, warm and fully heat soaked.

The car doesn’t only need to run properly for the first five minutes.

It needs to run properly when it’s actually being used.

🇦🇺 UP & GO TUNING
Holden | GM | LS
Road & Remote Tuning Australia-Wide
HP Tuners | Custom ECU Calibration | Data Log Analysis

01/09/2026

HOW WE SEPARATE A MECHANICAL FAULT FROM A CALIBRATION FAULT

One of the biggest mistakes in tuning is assuming that every problem with an engine is a calibration problem.

Sometimes the tune is wrong.

Sometimes the engine is wrong.

And changing calibration tables won’t repair a mechanical fault.

When we’re diagnosing an LS, we start by looking at what the ECU is actually seeing.

If the engine is showing abnormal MAF, MAP, fuel trims, lambda, injector pulse width, load, spark or idle control, we don’t immediately start changing tables.

We look at how the parameters relate to each other.

For example, if the MAF is reporting an airflow value that doesn’t agree with the engine’s operating conditions, we need to determine whether the MAF calibration is wrong or whether the sensor, housing or intake system is causing the problem.

If fuel trims are heavily positive, that doesn’t automatically mean “add fuel.”

We need to determine whether we’re dealing with an incorrect MAF curve, unmetered air, an exhaust leak, insufficient fuel pressure, injector problems or another issue.

The same applies to MAP.

If manifold pressure is higher than expected at idle, it could be an airflow calibration issue — but it could also be a vacuum leak, incorrect cam timing, valve-train issue, mechanical wear or simply the characteristics of the engine.

Then there’s misfire and knock.

If we see knock re**rd, we don’t just remove the knock control or pull timing until the number disappears.

We need to establish whether the engine is actually experiencing combustion knock, a false knock event, a mechanical noise or another condition.

The same diagnostic approach applies to idle problems.

If an engine is hunting, stalling or struggling to control RPM, we look at idle airflow, throttle position, spark correction, MAP, fuel trims and RPM response.

If the ECU is commanding more air and more spark but the engine still can’t maintain the target RPM, that’s telling us something.

The data can show us what the ECU is trying to do.

It doesn’t automatically tell us that the ECU is the cause of the problem.

That’s where proper diagnosis comes in.

A calibration problem generally follows the changes we make to the calibration.

A mechanical problem usually doesn’t care what table we change.

If we correct the calibration and the behaviour doesn’t respond as expected, we stop changing tables and start looking at the hardware.

Compression.
Vacuum leaks.
Fuel pressure.
Injectors.
Sensors.
Ignition.
Valve train.
Cam timing.
Throttle body.
Exhaust leaks.

That’s why data logging is so important.

We’re not using the log to find a number to change.

We’re using it to establish what the ECU is seeing, what the ECU is commanding and whether the engine is responding correctly.

Because sometimes the best tune is no tune at all.

Sometimes the correct answer is:

Fix the mechanical problem first. Then we’ll calibrate it.

🇦🇺 UP & GO TUNING
Holden | GM | LS
Road & Remote Tuning Australia-Wide
HP Tuners | Custom ECU Calibration | Data Log Analysis

01/09/2026

WHAT WE CAN ACTUALLY SEE FROM YOUR HP TUNERS LOGS

A proper HP Tuners log can tell us far more than whether the AFR looks good.

The important part is understanding how the ECU is arriving at its decisions.

On an LS, we can analyse MAF frequency, MAF airflow, MAP, RPM, IAT, ECT, calculated load and cylinder air mass together. We’re looking at whether the ECU’s airflow calculation is behaving logically as engine speed and load change.

The MAF sensor gives the ECU a frequency signal. The MAF calibration converts that frequency into an airflow value. From there, the ECU uses that information within its airflow and torque calculations.

If the MAF frequency increases but the calculated airflow relationship doesn’t make sense, that’s a calibration problem worth investigating.

We can then compare that against MAP and calculated load.

MAP isn’t simply a measurement of airflow. It’s manifold pressure. When we compare MAP against RPM, IAT, MAF airflow and cylinder air mass, we can start seeing whether the ECU’s model of the engine actually makes sense.

Fueling gives us another layer.

We’re looking at commanded lambda, measured lambda, STFT, LTFT, injector pulse width, injector duty cycle and fuel pressure where available.

For example, if commanded lambda is stable but fuel trims are moving heavily positive, the ECU is adding fuel because the measured result doesn’t match what it expected. That could point towards airflow calibration, injector characterisation, fuel delivery, an intake/exhaust issue or another underlying problem.

Then we look at spark.

Base spark, commanded spark, final spark and knock re**rd can show whether the timing we’re asking for is actually reaching the engine.

If the commanded timing is 24° but the engine is actually receiving less because of knock re**rd, torque intervention or another spark modifier, simply looking at the main spark table won’t tell you the full story.

Electronic throttle control is another big one.

We can compare accelerator pedal position, throttle position, commanded throttle and torque-related parameters to see whether the ECU is giving the driver the airflow being requested.

If the driver is demanding 80% throttle but the throttle blade is being commanded somewhere completely different, we need to understand why.

On a 6L80, the log can get even deeper.

We’re able to analyse commanded gear, actual gear, input/output speed, shift timing, TCC slip, torque reduction and transmission-related pressure parameters where supported.

That lets us see what the transmission is doing during an actual shift rather than simply saying:

“It feels like it shifts hard.”

We can look at the event and determine what the ECU commanded and what actually happened.

That’s the important difference with data logging.

We’re not looking at individual numbers in isolation.

We’re looking at relationships.

MAF → airflow → cylinder air mass → load → fueling → spark → torque → throttle.

And on the transmission side:

Engine torque → torque reduction → shift command → clutch event → converter operation.

That’s why the right HP Tuners log is so valuable.

The ECU is constantly calculating, correcting and intervening.

Our job is to read those calculations, identify what is actually happening and make a calibration change based on evidence.

**We don’t tune the number we want to see.

We tune what the data is telling us.**

🇦🇺 UP & GO TUNING
Holden | GM | LS | 6L80
Road & Remote Tuning Australia-Wide
HP Tuners | Custom ECU & Transmission Calibration | Data Log Analysis