09/10/2026
💥 DANGER MAP 💥
Just because your car has been tuned, makes good power and feels fast doesn't necessarily mean the software behind it is doing what it should.
This MINI arrived with an existing Stage 1 tune from another company. Before carrying out our own custom tuning, Chris decided to take a closer look at the previous software to see exactly what had been changed.
What he found was concerning and it's a good opportunity to explain why the numbers on a dyno graph aren't the only thing that matters.
What we found:
1. Fault codes had been switched off unnecessarily.
The previous tuner had disabled fault codes relating to decat and sports cat modifications, despite the car still having its standard catalytic converter fitted.
Your ECU is constantly monitoring different components and systems within the engine. When something isn't working as expected, it can trigger a fault code to help identify the problem.
By switching off certain fault codes, you're effectively telling the ECU to stop reporting particular problems. This means a fault could develop without the usual warning being given.
There was absolutely no reason for these codes to have been disabled on this car.
2. Load limits had been set too high.
Think of load as how much work the engine is being asked to do.
The ECU has various limits built into its software to control how much load the engine can request and produce under different conditions.
On this calibration, some of those limits had been increased beyond what we consider appropriate for the engine, with other related limits not correctly matched.
This can result in the ECU requesting more from the engine than it should under certain conditions, potentially increasing stress on components such as the turbocharger and engine internals.
Increasing limits doesn't automatically make more power. They need to be calibrated correctly and work together.
3. Temperature protection had been removed.
This is one of the more concerning findings.
Your engine has built in protection strategies designed to react when certain temperatures become too high.
For example if you're driving hard for a prolonged period and temperatures start climbing, the ECU can intervene to help protect the engine.
Think of it as a safety net.
The previous calibration had removed temperature protection maps, meaning some of those safeguards would no longer operate as intended.
The car might feel absolutely fine during everyday driving, but when it's pushed harder or driven in hotter conditions, those protections become particularly important.
We don't believe removing important engine protection strategies is an acceptable way of making power.
4. Pop and bang settings had been changed incorrectly.
Pop and bang software works by altering how the engine behaves when you lift off the accelerator.
It's not simply a case of switching on a few settings and suddenly getting exhaust noise.
On this calibration changes had been made to the relevant settings without correctly implementing the additional ignition re**rd needed for the intended effect.
This can cause unwanted behaviour such as revs hanging when you lift off the accelerator.
Depending on how the engine is operating, incorrect overrun calibration can also increase the risk of fuel washing oil away from the cylinder walls, known as bore wash.
That oil is there to lubricate and protect the engine. If it gets washed away, friction and wear can increase.
5. The engine was being given too much fuel.
More fuel doesn't always mean more power!
Your engine needs the correct mixture of air and fuel to burn efficiently. This mixture is controlled through something called lambda.
The previous tuner had set the fuelling excessively rich in certain areas, including at full load and at higher RPM under partial load.
In simple terms, the engine was being instructed to use more fuel than necessary.
This can cause several issues, including increased fuel consumption, spark plugs becoming contaminated with deposits, and less efficient combustion.
In more extreme circumstances, excessively rich running can also contribute to fuel dilution of the engine oil and increased engine wear.
A richer mixture can sometimes be used deliberately for component protection, but there is a difference between correctly calibrated fuelling and simply adding excessive amounts of fuel.
We removed the tune and Chris developed our own custom Stage 1 calibration, correcting the issues identified in the previous software, retaining appropriate protection strategies and ensuring the various load limits and fuelling targets worked together correctly.
📊 Stock: 209.5HP – 329.8Nm
📉 Previous Tune: 262.3HP – 406.7Nm
📈 DervTech Stage 1: 278.9HP – 425.3Nm
An additional 16.6HP and 18.6Nm over the previous tune. We haven't made that extra power by simply removing safety features or pushing every limit as high as possible.
A dyno graph can show you how much power and torque a car produces, but it cannot tell you whether the software has been written correctly.
You could have two cars making exactly the same power, but one could have properly calibrated protection strategies, fuelling and load management, while the other has had important safeguards disabled.
From the driver's seat you might never know the difference until something goes wrong.
This is why Chris spends so much time analysing datalogs, understanding how the ECU responds to changes and developing our software rather than simply chasing the highest number.
A good tune isn't just about how much power your engine makes. It's about how that power is achieved and how the engine is managed while producing it.
And that's something we take very seriously at DervTech.
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DervTech Tuning
🏠 Unit 3, Brimoto Trading Estate, Rossbank Road, Ellesmere Port, CH653AN
📞 0161 706 0586
📧 [email protected]
💻 www.dervtech.com
