Engine remapping has long been a taboo subject, but the increase in professional remapping services tailored to the tractor’s engine and drivetrain has meant it is now a popular method for farmers wanting to increase the power of existing tractors.

The benefits of boosting power of existing machines can mean that farmers can retain the services of a current tractor, but by safely equipping it with extra power and torque, it allows the operation of wider or heavier machinery to increase work efficiencies.

To understand the basics of remapping and help avoid the pitfalls, we spoke to Gareth Jones at Avon Tuning, who has been providing an engine remapping service for agricultural vehicles for over a decade and have a global network of authorised agents

What is engine remapping?

Engine remapping is the process of editing the engine control unit (ECU) to alter the characteristics and performance of the engine. A typical remapping process would result in increased power and torque, however peak power does not necessarily have to be increased. Operators may require more power in the mid-range, or additional torque lower down in the rev range but may wish to keep the peak power and torque as set from factory, in this case, a remap can be customised to suit these needs.

How does it work?

Remapping is very different to fitting a chip or a tuning box, which would have accounted for a large proportion of the market around seven to 10 years ago. A tuning chip or box will interrupt and manipulate the signals sent from the ECU to the engine, whereas remapping alters the ECU output at source. Editing at source rather than interrupting the signal is the way motorsport teams achieve huge powers from racing cars.

What parameters are changed?

When remapping a tractor there are dozens of maps inside the ECU which need to be carefully edited to ensure smooth and safe power delivery. These maps can be categorised into three main categories: fuel delivery, turbo boost pressure, safety limiters. 

• Fuel delivery

Modern common rail diesel engines have injection pressures up to 2,000 bar, whereas older machines would have been nearer 200 bar. The increased pressure gives a cleaner and more efficient burn. However, increasing fuel delivery is not as simple as just increasing the pressure, accounting for injection duration and timing as well will maximise performance and efficiency.

• Turbo Boost Pressure

The extra fuel injected needs more oxygen to maintain the air-fuel ratio, which is achieved by increasing the turbo boost pressure. Most modern tractors have electronically controlled turbo actuators allowing the ECU complete control of the boost pressure delivered to the engine. For most applications, boost pressure only needs to be raised marginally e.g.,100 – 200 mbar.

• Safety Limiters

Modern ECU’s have multiple safety limiters integrated into the ECU software – torque limiters, exhaust gas limiters, turbo pressure limiters – these limiters are there to protect the engine from mechanical failures or operator error. They need to be edited during the remapping process but must be modified in a safe and methodical way. They should never be removed completely.

Why are tractors detuned in the factory?

When tractors leave the factory, they are cautiously setup in relation to power outputs so they can reliably operate in extreme environments as well as on a typical UK farm. Tractors have multiple fuel maps to account for temperature peaks, so the ECU will use a map tailored to the outside conditions.

Can remapping be unsafe?

No, if the installation and map editing is carried out by an experienced engineer. Getting good power in the correct way is hard and requires dedication and research, however there are shortcuts used to achieve similar results, but the long-term damage it does to the engine and running gear are costly.

It is also worth bearing in mind that if someone says they’ll provide you with a new map then it is worth questioning where that map has come from. We take copies of the tractor’s original map and edit these, rather than installing a completely new map. We also save an original copy, so the machine can be returned to factory settings.

Can any tractor be remapped?

Yes, provided there is an ECU and the ECU is not locked. We work with Avon’s 50+ authorised agents to spot any weak components within a drivetrain of specific models. For instance, if a model has a known transmission fault, this guides us when building new maps to not put undue stress on the drivetrain.

The fuel ratio throughout the rev range can be modified to achieve the most efficient gains and this will also identify any restrictions in the fuel injection process, such as small injectors limiting power gains.

A common area we are advising customers on lately is where horsepower ratings and engines cross over different model ranges. A New Holland T6.180 Tier 4a has the same 6.7-litre engine as the whole of the T7 range, so it is reasonable to suggest that the engine is capable of the same power output as the T7.250.

However, the T6 range has smaller running gear than the bigger T7s, so adding this kind of power would put stress on the components and cause premature failure. Therefore, knowing what the model is capable of is an essential part of our work.

We will also check the part numbers of the main components correlate with any previous maps we have on the system. It is common for John Deere to use the same transmissions across a lot of its mid horsepower models, but not checking this could result in unnecessary damage.

The hardest machines to remap are the top of the range models, as there will only be small increases possible due to them leaving the factory near the peak of the safe working limits. Conversely, remapping the bottom of the range offers more possibilities as there is usually a big engine and transmission running well below its capacity.

What is the install process?

An install is carried out on-farm in around two hours and involves downloading the original maps from the machine’s ECU. Once downloaded, the authorised agent uploads it to Avon Tuning’s website portal with details of exactly how much power and torque is required.

From here it is downloaded by the team of software engineers at Avon Tuning’s Bristol HQ and the map is edited using similar data from previous remaps on identical models. There is no one size fits all with remapping and every tractor is different, but through experience we know exactly what is required to increase a New Holland T7.210 by 30hp.

What is backup like?

All Avon Tuning remaps come with a lifetime warranty against software malfunctions, which means the user is covered should there be any issues with the remapping technology. Installing a sophisticated remap from a professional supplier that is tailored to the tractor will have no detrimental effect on reliability of the engine.

Can it increase fuel efficiency?

Depending on the specific model and the type of work it undergoes, increasing fuel efficiency is often possible, however there are greater benefits to increasing work efficiencies. Being able to use the same tractor to pull bigger, wider implements or haul trailers up hills quicker can help complete the same job in a shorter time.

A low powered machine working at the top of its rpm range is being driven hard and could be using more fuel than it needs to. However, by adjusting where and how the fuel is delivered to the engine will allow the tractor to power the same implements at lower rpm or in a higher gear, thus reducing fuel use.

Does remapping invalidate a manufacturer’s warranty?

A manufacturer will almost certainly void any warranty if a remap has been carried out without approval, so it is advisable to speak with your dealer before any work is undertaken. If there is a good understanding between you and the dealer, then it may be that a warranty can still be actioned.

There has been a substantial increase in demand over the past five years for remapping in agriculture. Of all the machinery remaps we carry out, around 20% of the machines are still under a manufacturer’s warranty.

What does it cost? 

Prices reflects the complexity of the job and will depend on if the customer wants a simple stage 1 remap or a larger stage 3 remap and a full dyno test. Prices range from £500 up to £1,000.

What else can remapping offer?

Next Level Up Remapping

This has become very popular over the last few years, and instead of Avon remapping the tractor with our settings, we apply a map from the next model or few models up which uses the same engine and running gear. Farmers are familiar with model numbers, and it is now common for users to buy a smaller model in the range, such as a Class 630, and ask us to install a Class 650 map.

CNH Boost Locking

A common bugbear of New Holland users is that the boosted horsepower number on the bonnet is only accessible when the PTO is engaged and wheels are turning, which means it will never be available on haulage work or stationary PTO jobs. When we apply our Boost Lock map, we programme the ECU to deliver the power of boost mode under all conditions, so a T7.210 has 210hp when you need it.

AdBlue Delete

For the export market, tractors are likely to fetch a higher value if the AdBlue has been bypassed, especially if they are being sold to countries that don’t have the same emissions restrictions as the UK. It could increase the potential market for a tractor if it has been removed.