ECU Upgrades

Engine Tuning


The Basics of Engine Tuning i.e. ECU Remapping

An ECU contains the instructions for the fuelling, camshaft position and ignition timing systems to operate based on engine rpm and load. These instructions are known as 'THE MAPS'. Changing these instructions requires us to change the maps.  Hence the word - ECU remapping.

ECU remapping can be carried out through the diagnostic ports or by removing the eprom (chips) from an ECU. Chipping and mapping achieve the same end result.

Car manufacturers have to allow a general safety margin for poor fuel grades and extremes in climatic conditions. They also have to cater for a wide audience who have varied driving styles. Some cars are programmed with an extremely lazy throttle response for those who like it ultra smooth. This doesn't help the enthusiastic driver. Improving throttle response alone can make a huge difference. If you have a Mercedes this really applies to you!

With the use of good fuel grade, power can be improved upon whilst still factoring in some safety margins to minimise the effect of extreme climatic conditions. How much safety margin to leave depends on the experience of the tuner and their means of testing (dyno and real life testing).


Are all ECU Remaps the same?

Just because one ECU remap power claim is equal to another this does not necessarily mean you are getting the same thing! Many people base their decision on the power quoted alone - this is by far the worst way to decide on which remap to choose.

Firstly, power isn't everything. More important is the way the car will drive after the changes have been made. How many of the maps have been altered to work in harmony with each other. This again is down to skill, experience and R&D.

A remapped car by company A will probably drive different to one mapped by company B.


Custom Remapping

There is plenty of talk and type regarding 'custom' remapping. Engine tolerances are extremely small - we know this because we dyno so many cars and one car of the same model will always deliver pretty much the same power (as another as long as the adaptive values are set to zero).

Therefore there is absolutely no reason to custom remap every single 'stock' car. The engines are the same, the vehicles are the same. Our heavily developed ECU software will work the same in each stock car it is fitted to.

Custom mapping is only really beneficial to cars with major changes made to exhausts (headers) or engine internals. Air filters and induction kits do not require remaps. If an induction kit allows more air into the engine then the air mass meter will pick this up and generate the appropriate signals to deliver the correct amount of fuel.

Custom remapping a standard car for which we have already created a very good map is a useless and pointless exercise (apart from revenues gained by unscrupulous tuners) unless engine tolerances between car to car are very high.


Live Remapping

A highly misunderstood and misrepresented process in the tuning industry. Live remapping cannot be done through the OBD port. Live remapping means making changes to the ECU whilst the engine is running and this usually requires one of the following:

- Piggyback ECU

- Aftermarket ECU

- Emulator (these are usually soldered directly in place of the chips/eprom(s) inside the ECU)

Live remapping is like custom remapping in that it's only required for the same reasons as custom remapping would be.


Are ECU Remaps Invisible?

The simple answer to this is NO.

Sadly a majority of chip tuners and tuning companies claim that their ECU remaps are invisible to dealers. Whilst some of them claim that they are invisible to diagnostic equipment only, others insist they are totally invisible.

It is true that diagnostic equipment will not detect any changes to the ECU program, however, it is not true that dealers do not have the ability to detect changes. As an example, Evolve can simply take a read of ANY ECU and tell you whether or not it's been remapped. Now, if we can do this then a main dealer most certainly can.

There is no magic code that can or will hide changes made to the ECU program. The best solution is to load on your original ECU software and not run any warranty risks.


Chip Tuner Power Claims

You will find scores of independent 'chip' tuning' companies across the internet.  Many will have long lists of cars showing how much power can be achieved from them by plugging into the OBD port or removing the ECU.

A majority have no dyno facility.  So how is it they know how much power their upgrades will actually achieve?  The simple answer is that they have no idea. Some of the power gains are totally unrealistic. Unfortunately the industry over the last few years has devalued the meaning of true well engineered ECU remapping. One company after another has acquired generic chip tuning tools and literally added a few hp to their database over another chip tuners claims.  What you are actually getting in most cases is nowhere near what's being quoted as it's completely unrealistic.  This has therefore massively devalued what real horsepower and torque actually deliver.  Customers believe they are getting 10-15bhp from their engine, they cannot feel it and that's because it's not being delivered. They naturally believe that 10bhp doesn't make much of a difference.

We can assure you, that even on a 420bhp BMW M3 an additional 10-15bhp does not go without being noticed!

How do we know that other tunes are not realistic in their stated power outputs? We dyno test many cars on dyno days and general day to day business.  We are also part of the Dyno community and we share results.

At Evolve we have always quoted realistic power gains from the beginning and we regularly have enquiries where customers ask us how it is that on some cars, we quote amongst the lowest power gains in the industry.

We are realistic and honest in our power gains (it's the only approach to have) and we do not follow what others are doing in the industry. They may fear they will not acquire business if they don't quote what everyone else is quoting. Evolve and other like minded tuners have proven this is not the case.


Dyno's are extremely powerful tools and any major tuning company will own one. They are the ultimate tool for evaluating changes made to any aspect of engine tuning.

Dyno's are not harmful to your car.  This is a myth circulated by companies who do not wish to (or cannot) invest in these machines.
As long as adequate cooling is provided, which in our case is brilliant, no harm will come to your car.

Dyno's do not cause more stress to a car either.  This is another myth.  If you ever watch a dyno run you'll notice that the car accelerates far quicker through the rpm range than it does on the road.  It is therefore under less stress than the road.  Dyno manufacturers would not create equipment that costs hundreds of thousands of dollars that ruin cars.

For cars that can be live remapped they offer the ultimate in precision tuning.  In addition to this, if the engineer has the correct strategy for tuning they can extract the maximum power from the engine with the largest safety margins. However, it is essential that the cooling provided to the car/engine is enough to keep temperatures which are cooler or as good as what they are in the real world.  Without adequate cooling a dyno facility is not very useful.

So how do we know if the Evolve dyno and Dastek cooling fan are good enough for any given application? We datalog air intake, coolant and oil temperatures under normal road conditions.  We then datalog what we are getting on the dyno.  If the temperatures are within a few percent then that particular car is fine on the dyno. In most cases we have found that our setup can replicate road conditions and therefore whatever gains we see on the dyno will most definitely be translated to the road.

If a company is serious about it's tuning they will have a dyno.

Dyno Power Outputs

Dyno power outputs can be manipulated. Unfortunately some companies do manipulate dyno readings in order to show a false gain.
Any company who values their reputation will never manipulate dyno results. There are hundreds of dyno's worldwide and it's easy for you to dyno your car before and after your car has been upgraded and compare the results of the independent dyno and the tuners' dyno.

The latest Dyno Dynamics machines make it very difficult to manipulate power outputs and this is one of the reasons we purchased one.  However, they are still open to abuse BUT it's extremely easy to get caught out as all of the atmospheric conditions are recorded for every dyno run (so ensure they are presented on your printout, otherwise they may be hidden for a reason!)

All of the above is a very general guide.

If you would like to understand things further please do not hesitate to contact us and we'll take you through everything in more detail.

Thanks for Reading!
The Evolve Team