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The old argument: tuning boxes vs remapping

Electric car plugged in for charging
(Image credit: Mikes-Photography from Pixabay )

Improving engine performance is fast becoming a popular hobby for many motorists - especially today as car modification can even be done at home. As such, the old age argument of tuning boxes or remapping has reared its head. Tuners, petrolheads and car forums have long been arguing and discussing the potential for both when it comes to improving engine performance, torque and power, yet many are still unsure of the route to take. However, we are answering the argument once and for all…

Tech in the car industry

Tuning boxes and car remapping are just several examples of technology reforming the car industry. For instance, the automotive industry and technology companies have been working hand in hand for many years, to deliver the most innovative, hard working and safe vehicles. 

Cars are, largely, becoming smart devices with better fuel efficiency and more. Tuning boxes, for example, are popular for this reason, altering the ECU to provide more power. However, while we wait for driverless cars and the like, you can still enhance your vehicle and satisfy your need for speed.

How do I improve my car performance?

Since the initial launch of Max Power magazine and the days Pimp My Ride burst onto the scene, petrolheads have been looking for ways to improve and modify their vehicles. When it comes to enhancing power in your diesel or petrol engine, there are two primary routes to alter the ECU: tuning boxes or car remapping. 

The tuning box - designed for both petrol and diesel engines - works by changing the signal between the ECU software and the fuel injection system. The alteration ‘tricks’ the ECU into increasing the quantity of fuel injected, enabling it to boost pressure, therefore resulting in more torque and power. However, car remapping directly alters the ECU software. The remapping procedure is entirely permanent - many dealerships will find evidence the car has been modified.

Tuning boxes vs remapping

As mentioned above, technology is rapidly changing the face of the automotive industry. We’re also seeing more of a turn towards car leasing. Today, the number of UK cars on the road through a lease purchase is at its highest ever recorded, growing to 1.343 million in 2017 alone. The business sector has experienced a rapid increase of 8,000, equating to a 0.6 per cent growth, year on year. Therefore, the stats suggest a car tuning box - outlined below - is a more suitable option than vehicle remapping… However, we’re outlining the argument for tuning boxes here.

DIY tuning

When it comes to installation, a tuning box takes mere minutes. You can install the box yourself, with plenty of instructions and YouTube guides available online. While there are professionals able to help install the box, there is no reason you cannot do it yourself - even without professional tutoring or previous skillset. However, modify the ECU and remap your car yourself, and you could be causing more damage than good. In fact, you could cause irreparable damage to the engine and void your warranty.


As mentioned earlier, a car remapping can void your warranty - you must be careful. Each new car will come with a warranty as standard, with varying lengths. However, most will last for an average of three years. 

The objective for the warranty is to ensure mechanicals, such as the engine, gearbox and electrical system, work as they should. As the engine is covered in the warranty, you could be running the risk of losing money by modifying the ECU. The ECU, essentially, controls how the engine works. 

A remapping then works by permanently altering the software to enhance torque and power. The values in the map are re-written, and undeniable evidence is left on the ECU. Today, technology is being used to pick this type of modification up automatically on the dealer diagnostic tool, immediately informing HQ - without even the need for the dealership to do so. Therefore, the manufacturer can see this and, of course, void the warranty.

As long as you remove your tuning box before a dealer visit, there should be no trace it was ever installed.

Many newer models prevent remapping

Of late, many manufacturers are working to ensure remapping is not possible on specific models, and encrypting the ECU. In simple terms, they are putting a ‘password’ on the engine unit. Until this is cracked and you get through, you cannot edit the ECU tables, meaning a remap is not possible.


A major advantage to a tuning box is the lack of trace. The box is, literally, fitted to the vehicle to change the signal as it passes between the ECU, fuel injection system and boost sensor(s). It can be removed once you change cars, with the vehicle returning to standard. On the other hand, However, remapping the ECU is evident, and manufacturers can see that you have done so. For those that do have their car through lease, you need to consider whether it is worth the additional costs.

Petrol tuning boxes

There is a wealth of information available on the benefits of tuning boxes for diesel vehicles, but petrol tuning boxes are growing in popularity also. While Bluespark Automotive has noticed a 6 per cent increase in the rise of diesel tuning boxes, they have noted a staggering 379 per cent growth in the number of people purchasing petrol tuning boxes since 2017. Modern turbo petrol engines are an ideal candidate for tuning - particularly as they respond extremely well to the tech.

It’s also important to note the costs of a potential full car remapping, and the cost of buying a box that can be removed and reused once you change cars.

Ultimately, a tuning box is a temporary modification - benefiting those who do not own their car - while the remapping software will cause significant changes to the ECU. Similarly, the box is easy to install and remove. We suggest weighing up all options before opting for one above another.


Further reading

In a range of features, we explore automation in the car industry, including: what lies ahead for the future of self-driving cars (opens in new tab); how software-defined vehicles are revolutionizing what it means to own a car (opens in new tab); how AI and automation could tackle the UK's collapse in car manufacturing (opens in new tab); how connected cars are driving vehicles towards an autonomous future (opens in new tab); how 5G is enabling the era of data-driven vehicles (opens in new tab); and how autonomous vehicles will evolve over the next decade (opens in new tab).

Edd Fisher is a Director at Bluespark Automotive.