RAC Cars News


What's engine remapping all about?

By raccars Published

Image Source

Remapping or chipping your engine is usually carried out to boost performance and improve fuel economy, but it can also cause some problems. The amount of power you can squeeze out of your car is not limited by how far you can get your pedal down but by your car's ECU or engine control unit and the software it is running.

'Chipping' used to be the boy racer's speciality, but these days remapping is available to anyone simply by looking online. There are lots of companies offering the service and you should do your research carefully to make sure that you use a reputable provider.

Engine control units

These days even the most basic cars contain ECUs running sophisticated computer algorithms. These control a number of engine functions including ignition timing, the boost pressure from your turbocharger and the air to fuel ratio. When you buy a car, these are set to factory levels in order to comply with stated power outputs, fuel consumption and emissions, but most cars can in fact be tuned to exceed factory settings. Manipulating your ECU's settings can result in extra performance and greater fuel economy; this process being referred to as engine remapping.

What are the benefits of remapping?

A number of companies specialise in changing the software used by your car's ECU in order to adjust performance restrictions. This used to be achieved by changing a circuit board or a chip within the device but these days new software is uploaded from a laptop or handset using a diagnostic port on your car.

The results can be dramatic - for only a few hundred pounds you can apparently take the power output of a Mk6 Volkswagen Golf Gti from its factory setting of 207bhp and 280Nm of torque to 251bhp and 324Nm of torque. In a turbodiesel a remap can improve fuel economy by up to 10 per cent by increasing lower range torque.

In many cases you will need to take your car to engineers to carry out the remapping but you can also buy a remap, sometimes in the form of a plug-in kit, which allows you to upload the re-installed software yourself. After remapping you can restore factory settings if you need to and without the help of a technician.

What are the problems?

Buying a remap from a reputable company shouldn't cause your car any mechanical problems as the software is carefully developed to ensure that it doesn't exceed the acceptable parameters of your engine's capabilities. Essentially, remapping is quite often what manufacturers do when they release a higher performance version of an existing model rather than develop a new engine every time. Earlier models have usually been limited with respect to performance, and those limits are simply raised for subsequent models in order to offer extra power.

You should of course inform your car insurance company if your car has been remapped, but these days this isn't necessarily a problem. In the past remapping raised a big red flag with most insurance companies but it is becoming more common and more acceptable among insurers. There are still some who won't insure a remapped car; whilst others may increase your premium slightly.

Bear in mind that a remap will invalidate any warranty you have on your car, which usually only applies to newer models. If you really want some extra power on a new car, it's probably safer to wait for the higher performance version to be released.

Looking to Buy?
Search for cars