Remapping FAQ

Posted by Nick Cook on

Technician remapping car

What is remapping a car?

A remap is purely extracting what existing power is left within the cars parameters for its current level of hardware, meaning if the car is completely stock then the remap should be designed to suit the stock components. This is done by replacing the standard software on a cars engine control unit (ECU).

If the car having the remap done has supporting hardware such as performance intercoolers, upgraded induction kits and aftermarket exhaust then the parameters within the ecu can be pushed further, thus the engine will produce more power and torque.

Is a remap bad for my car?

Isn’t this the big question!!

If the remap calibration is designed by a specialist and put through a rigorous research and development program the short answer to “is a remap bad for my car?” is of course no.

Cheap remaps are generally the problem causes, although there is no rule for the cheaper the remap the more likely it is to be a problem causer. Generic remap files are usually bought from a remap file support server on the internet and are usually untested and flashed directly to a cars ecu, these file services are available from as little as £50.00 to a typical remap flashing company.

Typically, a company selling maps flashed without any dyno proof are using cheap generic remaps bought online from a file providing service. You may also find that these companies are not datalogging your vehicle (click here for a more detailed what is data logging video). Without this precious data they are essentially letting the car go back to the owner completely unaware if the remap they have flashed is safe at all.

Will a remap make my car faster?

Ultimately this depends on the quality of the remapping calibration. Engine control systems on modern vehicles are extremely complex and extremely capable when it comes to safety during the building of a remap file.

Imagine an engine as a big pump that sucks in air, injects fuel, compresses the air, ignites the mixture then the final stroke expels the combustion gasses. Improving this process by adding a performance induction kit and an aftermarket exhaust allows the engine to breathe freely, increasing the air intake and allowing the gasses to be exhaled faster. Your vehicle will then be able to handle more ignition timing and therefore produce more power.

On turbocharged applications an upgraded intercooler can greatly reduce charge temperatures across the core usually due to its better construction whether this mean core density, design or thickness.

Technician Remapping a Seat Leon Cupra R

What do the stages of tuning mean 1,2,3?

Quite often in the modern car modifying and car tuning world people will use tuning “stages” to identify what level of remap and hardware they have installed on the vehicle.

This was something that tuning companies started to institute to help potential customers understand what level of hardware was required to meet a specific state of remap/tune. It also meant that packages of aftermarket hardware and software could be made available with quoted power figures.

Let’s get into the specific stages:

Stage 1 Tuning

This denotes a completely stock vehicle as it left the factory where the ECU is remapped with a bespoke calibration to achieve its full potential without the requirement of any aftermarket tuning parts.

Stage 2 Tuning

This stage is a little more in depth requiring specific hardware depending on the make and model of vehicle but as an industry standard for a stage 2 remap you will require the following hardware upgrades:

These are the basic requirements; however, people also add big boost pipe kits, charge pipes, intake plenums etc.

Stage 3 Tuning

This is where things get interesting! You would need all the above aftermarket parts including performance intercoolers, performance exhaust aftermarket induction kit and so on coupled with a hybrid turbo.

Will remapping give me bad fuel economy?

This is a commonly asked question for people remapping a car who are worried about a negative effect on their vehicles fuel economy. At VUDU Performance, we are constantly asked if a remap will reduce fuel economy. Now this is a difficult answer so we will issue some brief pointers below.

You should expect to see a dip in fuel economy as you enjoy your increase in power from the remap process until you settle back into your natural driving pattern, at which point you should see improved fuel economy due to a much improved fueling table within the software.

A poor quality remap from a cheap file supplier could result in over increased boost pressure, which will require much higher demand on the fuel system to keep things cool and match the target lambda (exhaust gas reading) that has been specified within the software.

We often see bad fueling tables or boost pressures ramped up, which will intern give a higher torque figure giving the driving sensation that the car has lots of power. This will ultimately destroy any fuel economy particularly at cruising speeds where fuel trims should be relatively stable.

Ultimately if the ecu calibration (remap) is well written and tested correctly for your vehicle you will find a small improvement on fuel economy once you return to your standard style of driving. Couple this with the increased performance when it is required, and you should be very pleased with remapping the vehicle.

Without doubt any garage offering a remapping service should be able to power test the vehicle and offer you a printout of the results before and after the remap. This ensures that the delta gained between stock and tuned is what is quoted by your preferred tuning company.

Why should I have a remap done on a dyno?

Dyno test results

Couple this with the safety aspect of been able to conduct proper testing in a controlled environment and it goes without saying dyno testing is by far the safest way of having a remap done on your car.

There are discrepancies between dynamo-meters as with any product if the garage uses a cheap cooling fan or substandard rollers you may find the car is unable to achieve the desired results due to heat or under reading rolling road. There are also dynos in circulation that read too high. Whilst on the day this is very exciting as the car looks to be overachieving it can be disappointing if you visit another facility.

As a chassis dyno, the Dynapack at VUDU Performance couples directly to the wheel hubs and applies a precisely controlled hydraulic load. This method of direct coupling, plus its built-in strength, results in a huge number of benefits over a rolling road.

Read more about the VUDU Performance hub dyno on our blog here.

Need help with a remap?

Our expert technicians are on hand to to help, simply get in touch on 01924 228042 or email us at



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