Remap Services



Performance and Economy Ecu Remapping Service.


  • Flatspot removal
  • Speed limiter Removal & Activation
  • Clutch Protection
  • DPF Removal
  • EGR Delete

Ecu Re mapping
So why should I remap my ECU? When vehicles are distributed throughout the world, manufacturers adopt a one map fits all policy. This one map has to take into account many different factors that are necessary for each export country. Areas such as climate, emissions, fuel quality etc all have to be considered by the manufacturer. What this means is that a vehicle ECU is never optimised for one individual situation
The increase in power and torque that is gained using ECU remapping provides a much smoother drive, with increased flexibility throughout the rev range, allowing for smoother acceleration and better overtaking.

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“We always carry out a full diagnostic scan before

and after re-mapping any vehicle”

What kind of improvements can I expect? As mentioned you will notice an improvement in power and torque right throughout the rev range, along with the possibility of improved fuel economy. See below for a general idea of average improvements for different engine types:

Petrol (non-turbo) By remapping a normally aspirated engine ECU, you would normally expect to see a 10 – 15% increase in power (bhp) depending on your exact engine specification, and around a 15 – 20% increase in torque (Nm) throughout the rev range. This improves engine response on a lighter throttle.

Petrol (turbo) By installing a modified engine ECU map on to a turbo engine you would normally expect to achieve around a 20 – 30% increase in power (bhp), with an increase in torque of around 20 – 40% depending on your engine specification. The large increases in both power and torque will greatly improve the engine flexibility in all gears and throughout the rev range.

Diesel (turbo) Remapping a diesel turbo ECU normally sees the greatest gains of any engine type. Typically you will achieve an increase of 25 – 50% power (bhp) and around a 50 – 75% increase in torque depending on your engine specification. The engine response is greatly improved throughout the whole rev range and in all gears. Diesel engines are well known for providing huge amounts of torque and in gear performance. A remapped modern turbo diesel engine has the ability to embarrass many petrol engine cars under normal driving conditions.


Before removing your EGR it’s worth understanding what it does and why it is fitted.

Exhaust Gas Re-circulation occurs during light engine load. Hot gases from the exhaust are vented back in to the intake of the engine instead of fresh air with a higher oxygen content.

This hot exhaust gas actually acts in a similar manner to an inert gas under combustion. The inert gas causes a reduced cylinder temperature and also a reduction in peak cylinder pressure. The result of this is that less oxides of Nitrogen are formed during combustion (NOx).

The down side of exhaust gas re-circulation is that there is a slight trade off between fuel economy and NOx emissions. With EGR fitted an engine is actually slightly less efficient. To add to this car manufacturers also retard injection timing slightly as this also helps to reduce NOx. Again this has a negative effect on fuel economy.

Why remove the EGR?

Many HDI owners choose to remove the EGR not for the small economy gains, but actually as a preventative measure (or to fix an EGR fault).

At some point in your car’s life it’s likely the EGR will begin to cause a problem. Sometimes the inlet manifold can clog with dirt thanks to the dirty exhaust gases entering the engine, alternatively the EGR control solenoid can break causing 100% EGR at all times which will cause a large power loss and un-even running.

With EGR removal you should notice a slightly better pick up, this is thanks to a greater mass flow of clean air through the engines air flow meter, normally fresh air intake would be slightly reduced when air is diverted through the EGR system.

Is it worth disabling the EGR if there aren’t any problems with it currently?

This is entirely up to you, however it’s likely the electro valve will go wrong at some point in your car’s life and cause an EGR fault, so you may as well remove it as a preventative measure. You’ll also notice better pick up and slightly better fuel economy with the EGR removed.


Why is more power beneficial?

ECU tuning can be beneficial in many ways. There are several uses for a more powerful vehicle during day to day use. Some owners may require more power for safe overtaking manoeuvres. Others may need more power when towing heavy trailers or caravans. Some drivers may simply want to upgrade their engine without the need to spend money on a new vehicle.


How does a remap increase power?

The main power increase from a remap is the result of injecting more diesel into the engine when the driver requests full power. Alongside the increased level of fuel flow, there are other considerations:

Injection Timing – It is important to calculate the optimum start to the injection period. As there is an increased fuel flow entering each cylinder, the time at which it begins must be sooner to ensure that it can burn completely before the exhaust stroke.

Fuel Pressure– A small increase in fuel pressure yields two main benefits: The first being better atomisation of fuel, this promotes a more efficient burn, resulting in more efficient use of the fuel injected. The second benefit to a small increase in fuel pressure is that the length of the injection period will be slightly reduced. This allows for a greater flow of fuel to enter an engine in a time period whilst ensuring it can be burnt completely before the exhaust stroke.

Turbo pressure– Where applicable, turbo pressure is increased to give a greater mass flow of air into the engine. This means that more fuel can be burnt whilst staying within stoiciometric requirements, resulting in increased power output.

Is a remap safe?

Many modern vehicles are somewhat ‘under tuned’ when released from their factory. There are several reasons for this:

The first is that many car owners will not stick to the recommended service intervals for their specific vehicle. As a result of this, the engine oil could deteriorate and cause blockages in the oil lines. This could potentially starve the engine/turbo charger of oil. The fuel and air filters could also block, limiting the quality and flow rate of diesel. The manufacturers must account for these factors (and many others), and prevent damage being caused to the engine by an irresponsible owner.

Another clear cause for ‘under tuning’ a vehicle is to promote sales of future vehicles. If a manufacturer can improve the performance of their new vehicles year upon year, then it is likely that they will continue to sell their newest models and will continue to make profits.

As modern cars are equipped with an electronic control unit (ECU), it is possible for a ‘tuner’ to modify the data stored within it, and increase an engines performance safely. This is carried out in the same manner as the manufacturer would approach it if they were to ‘upgrade’ the power output of the vehicle.

All of our tuning has been thoroughly tested to ensure the safety and longevity of your engine. If more power is requested from an engine it is important that the service intervals are adhered to. This will help to prolong engine life.  We recommend cutting the service intervals to around 6K miles, just for peace of mind. If you look after your car, it will look after you!
What makes a remap safe?

When developing a remap it is important to monitor and log engine running parameters using data logging equipment. Through this, it is possible to ensure the high pressure fuel system (fuel pump, fuel pressure regulator, injectors, rail pressure sensor) and the turbo charger are able to operate as requested and calculated within the remap whilst remaining within safe limits.

It’s important not to inject too much fuel as this can raise Exhaust Gas Temperature (EGT) potentially causing damage to a turbo charger; all of our remaps are tested to ensure the EGT levels remain within safe limits.

It’s also important to be considerate towards a cars transmission, the rate at which torque is bought in and the maximum torque set is important. If you are worried you may have clutch problems it’s best to get in touch with us, generally we recommend fitting a new clutch if it is worn excessively, or alternatively we can produce limited torque remaps.

How do we do this? By using Viezu Maps

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