Civinco - tuning excellence. Engine management systems for all needs

In series
Modern vehicles with OBDII based PCM's and Can Bus systems can be a challenge to tune effectively when the vehicle has been modified.
We wanted our customers to have an enhanced driving experience as often as possible so the iEMS3 (integrated Engine Management System) was designed to produce gains across the entire RPM band, unlike other tuning solutions which simply modify the Wide Open Throttle range (WOT). Producing a higher RWHP & RWTQ number at 5500 RPM was not our goal as that RPM is rarely used. Simply inserting a pre-programmed Smart Card immediately changes the program settings for the current driving situation or octane of fuel

System Overview:
The BC system allows precise tuning of the air to fuel ratio and ignition timing over the entire operating range of the engine. Simply inserting a pre-programmed memory card immediately changes the program settings for the current driving situation or octane of fuel as desired. The unit contains its own fuel injector drivers and is wired in between the factory PCM and engine. It is especially useful for recalibration of both forced induction engines and those with extensive modifications, allowing the tuner to quickly get the engine running correctly. Stock engines can also benefit greatly from improving the fuel curves.
The BC-system is similar to a stand-alone engine management system, but also has similarities to current "piggyback" systems. It is actually a heavily modified Stand Alone Engine Management System that has been modified to work in conjunction with a factory PCM. We consider it as working "In Series" with the factory PCM, basically a supplemental fuel and timing computer system.
In a true stand-alone system, you must program for every operating condition the engine will experience, such as load, throttle position, RPM, engine temperature, air temperature, etc. These systems can be quite complex to tune. Most PCM’s also control radiator fan operation, A/C operation, emissions operation and diagnostic functions.
Stand-alones are generally not compatible with OBD2 emissions testing in that they replace the factory PCM and will not link up with state run emissions equipment. Nor will they allow functionality of the remainder of the modern Can Bus system. These systems are best suited for racetrack use where engine tuners can fine-tune the program to the environment of the moment for optimal performance.
In the current "piggyback" systems, control over the engine is done by manipulating inputs to the stock PCM. Manifold air pressure and oxygen sensor voltages can be altered in order to make the PCM change its load calibration, thus altering fuel and ignition advance curves. Reducing MAP sensor voltage has the effect of reducing injector pulse width by making the PCM "think" the engine is under greater vacuum than actual. This is MAP sensor voltage skewing in a crude and somewhat unreliable method of fuel control.
However, at the same time, ignition timing is advanced due to the PCM believing the engine is under a lower load. Conversely, increasing voltage has the opposite effect, increasing fuel and reducing timing advance. When tuning with systems of this type, you find yourself in situations where you can have proper part throttle tuning, or proper full throttle tuning, but rarely both if the engine is heavily modified or has forced induction. To make matters worse, today’s vehicles are too smart for such methods, and will simply readjust for any input that is a constant or repeatable input. This very quickly erases any changes that are attempted.
The current PCM file rewriting software that is on the market, works well on NA engines. However, due to limitations in the physical architecture of a Modern PCM, it is impossible to tune for all operating parameters when adding forced induction. This is due to the fact that a factory NA PCM just does not have the capability to be properly adjusted for a pressurized manifold state of operation. The only way to increase fuel during boost is to simply lower the WOT threshold which is generally a function of throttle blade opening percentage.
This has the effect of basically telling the PCM that the car is in a wide open throttle state when the drivers pedal position is no where near a similar position. When this occurs, the car simply wants to go right now, and lunges ahead. This makes it very difficult to operate when under light load situations, such as moderate acceleration, merging, shallow hills, etc. The effective travel range of the accelerator pedal has been greatly reduced. This can cause additional difficulties such as decreased gas mileage since the vehicle is running in an open loop mode with very rich fuel ratios when it should be in closed loop mode operation.
Since the factory PCM can not be written to actually understand boost, there will always be a window (in particular with a turbocharger) where the vehicle can be developing boost (part throttle boost), yet there is no fuel correction. Conversely, in trying to lower the WOT threshold as described above, you can wind up with extreme drivability issues, and it’s just not a fun vehicle to drive. To make matters worse, generally a 2 Bar or 3 Bar MAP sensor is added to prevent overanging the voltage signal sent to the PCM. This can have the effect of telling the PCM that the vehicle is seeing a much lower load than it really is, and can result in lowered transmission line pressures when you need it most. This is similar to the same problems found when using a MAP sensor voltage skewing "piggyback" system.
The iEMS3 offers the best of both worlds. Stand alone system control, but with the simplicity of a piggyback system. The iEMS3 controls fuel and timing, leaving the stock PCM to handle all other functions, such as idle speed, A/C control, emissions operation, etc.