Post by oldschool on Feb 27, 2007 17:57:39 GMT
There seems to be a lot of confusion when it comes to re-mapping and what re-mapping is about.
First of all, when we it is generally referred to re-mapping or chipping only a fraction of the ECU is affected by this process. Re-mapping does not alter the entire software information. The majority of the information stored in the ECU is needed to translate the information (changes in voltage) the sensors supply to help the ECU understand what the engine is doing and what it needs. With this information then the part of the programm, which corrects ignition timing (except Diesels) and the amount of fuel injected can be set for the required running of the engine.
This part of the software often is referred to the mapping grids. These can be split into individual planes, which are in the 3D grid either load planes or rpm planes. The x-axis refers to the amount of fuel units or ignition timing. As there is only a limited number of planes along both axis' the software has got to be geared up to interpolate all values that are between the planes on load and rpm.
In more basic and usually older generations of factory fitted ECUs only a few mapping grids are present. Later ones are blessed with more of them and currently designers seem to go mad on them.
Starting on a blanc ECU to get it to a stage that ensures safe running under all conditions is a very labourius task. Manufacturers have to spend in excess of £5,000,000 to get to that stage. To start with a blanc ECU for racing will require much less effort as the conditions never can vary as much as it is with a mass produced car. But even then it can take several months of testing before the antissipated results are achieved.
The reason why re-mapping can show improved results when done professionaly is many fold. Manufacturers have to consider many variables. These include
Fuel quality
Ambient conditions
Kind of use
Homologation requirements
Insurance requirements
Fuel consumption
Long term stability problems
Keeping emission control measures functioning.
All these variables do not allow for the 'optimal' setting as to many purposes have to be satisfied.
By just altering the map to get maximum power out of the existing hardware set-up might give some more power at the expense of one or more of conditions to be met. This is where re-mapping can take 2 directions. The inferior tuning route would use the max power school of thinking and just go for power no matter what the consequnces are, which inevitably will strike against the project sooner or later.
The professional direction would be to move within the parameters and achieve impressive results.
When doing the map on a standard car, specialist companies have spend a lot of time to get thes re-map done professionaly with the help of rolling roads and other technical means. These are usually referred to as generic maps.
When going further (applies to both Diesel and petrol) with the modifications a generic re-map won't be adequate anymore. The map can't reference properly anymore in relation to the modifications. In some cases rather basic modification such as an exhaust system or a properly designed induction kit might still show some improvement with a generic map, but will be quite some way off the optimal results, which only can be achieved with further testing. In many cases worse results will be seen. Some people are meant to believe that this can be done easily by testing it on the road, but experience shows that this does not occur in reality.
A much better way is to rely on the expertise of people who design packages, where a dedicated map is part of the package. If then more power is wanted the fine tuning stage can be entered giving it a bit more power.
When any further modifications are done then it is necessary to finally adapt the re-map accordingly.
First of all, when we it is generally referred to re-mapping or chipping only a fraction of the ECU is affected by this process. Re-mapping does not alter the entire software information. The majority of the information stored in the ECU is needed to translate the information (changes in voltage) the sensors supply to help the ECU understand what the engine is doing and what it needs. With this information then the part of the programm, which corrects ignition timing (except Diesels) and the amount of fuel injected can be set for the required running of the engine.
This part of the software often is referred to the mapping grids. These can be split into individual planes, which are in the 3D grid either load planes or rpm planes. The x-axis refers to the amount of fuel units or ignition timing. As there is only a limited number of planes along both axis' the software has got to be geared up to interpolate all values that are between the planes on load and rpm.
In more basic and usually older generations of factory fitted ECUs only a few mapping grids are present. Later ones are blessed with more of them and currently designers seem to go mad on them.
Starting on a blanc ECU to get it to a stage that ensures safe running under all conditions is a very labourius task. Manufacturers have to spend in excess of £5,000,000 to get to that stage. To start with a blanc ECU for racing will require much less effort as the conditions never can vary as much as it is with a mass produced car. But even then it can take several months of testing before the antissipated results are achieved.
The reason why re-mapping can show improved results when done professionaly is many fold. Manufacturers have to consider many variables. These include
Fuel quality
Ambient conditions
Kind of use
Homologation requirements
Insurance requirements
Fuel consumption
Long term stability problems
Keeping emission control measures functioning.
All these variables do not allow for the 'optimal' setting as to many purposes have to be satisfied.
By just altering the map to get maximum power out of the existing hardware set-up might give some more power at the expense of one or more of conditions to be met. This is where re-mapping can take 2 directions. The inferior tuning route would use the max power school of thinking and just go for power no matter what the consequnces are, which inevitably will strike against the project sooner or later.
The professional direction would be to move within the parameters and achieve impressive results.
When doing the map on a standard car, specialist companies have spend a lot of time to get thes re-map done professionaly with the help of rolling roads and other technical means. These are usually referred to as generic maps.
When going further (applies to both Diesel and petrol) with the modifications a generic re-map won't be adequate anymore. The map can't reference properly anymore in relation to the modifications. In some cases rather basic modification such as an exhaust system or a properly designed induction kit might still show some improvement with a generic map, but will be quite some way off the optimal results, which only can be achieved with further testing. In many cases worse results will be seen. Some people are meant to believe that this can be done easily by testing it on the road, but experience shows that this does not occur in reality.
A much better way is to rely on the expertise of people who design packages, where a dedicated map is part of the package. If then more power is wanted the fine tuning stage can be entered giving it a bit more power.
When any further modifications are done then it is necessary to finally adapt the re-map accordingly.