Wow this was written 10 years ago!
The PowerFC was a good system then and still is today. There's probably a few updates that 'newer' ECU's have but for a street car, it does pretty good....
Excerpt:
14th September, 1999
Over the last 12 months, AutoSpeed has carried out a 25,000 kilometre test of the APEXi Power FC engine management computer, supplied to us by JAP Trading. We've driven the car in ambient temperatures as low as 4 degrees C and as high as 45 degrees. At 260 km/h and at 5 km/h. When trying to extract the maximum distance from a tank of fuel - and when trying to extract the maximum number of kilometres from each hour. AutoSpeed staffers have driven the car, mechanics proficient in programmable management have driven the car, and people who regard a car as nothing more than transport have driven it. In short, this is a real-life test where every type of driving has been undertaken by a variety of people.
The Power FC
Unlike many Japanese aftermarket electronics products, the Power FC is not an interceptor and isn't packed full of useless gimmicks. It doesn't take the signal coming from the airflow meter or MAP sensor and alter it; it doesn't change output signals from the stock ECU as they head towards the ignition coil switching module; it doesn't have flashing LEDs and quaint slogans. Instead, it is a complete, drop-in replacement ECU - once it is fitted, the stock engine management ECU can be literally removed and placed on the shelf. Even better, the APEXi unit plugs straight into the standard loom, and uses all of the standard output actuators (injectors, idle speed control motors, etc) and standard input sensors (intake air temp, airflow meter or MAP sensor, etc). Even better again, the Power FC comes pre-programmed for each engine for which it is suitable, allowing the car to be started and driven straightaway. (However - as you'd expect - the standard program isn't suitable for all fuels and applications.)
On test was the PFCRB26, which is suitable for the R32 and R33 Nissan Skyline GT-R models. (A full list of the engines for which Power FCs are available is shown at the end of this feature.) Power FCs suit only Japanese high performance engines - none are made for European, Australian or US engines. The test Power FC measured 170 x 155 x 33 mm (HxWxD), making it a little smaller than the standard Nissan ECU in the GT-R. 'APEXi' is attractively stamped in the brushed alloy cover plate used on one side, meaning that the ECU could be prominently mounted for appearance, if that's desired. Inside, the APEXi unit is obviously much more electronically modern than the late-Eighties standard Nissan ECU. Extensive use is made of surface-mount components, for example, and unlike some plug-in ECUs, the component count and board complexity remains high.
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The APEXi Power FC is optionally supplied with a backlit handheld pendant LCD-type programmer. This uses a 60 x 30 mm dot-matrix LCD display, four arrow buttons and also 'previous' and 'next' buttons. The size of the LCD display and the dot matrix format means that far more information can be shown on the screen than is common with handheld pendant-type programmable ECU controllers. However, no handheld pendant can compare for information density with the amount available on a laptop PC colour display. Although there is a PC link and appropriate PC software available for the Power FC, apparently the software is in Japanese and so is not sold outside of Japan. This is the most major limitation of the APEXi Power FC - there's no optional English-language PC interface.
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The pendant is used for three functions - displaying engine data ('Monitor'), displaying and then reprogramming engine management maps ('Setting'), and an 'Etc' (sic!) mode. In its Monitor mode, any two of the following factors can be displayed on the screen: Injector Duty Cycle, Ignition Timing, Airflow Meter Output Voltage, Engine RPM, Road Speed, Boost Pressure, Knock Sensor Output, Coolant Temp, Intake Air Temp, and Battery Voltage. The pair that is displayed can be selected, so you can have Boost and Knock Sensor output, for example. In addition to displaying this data numerically in real time, a line graph function can be enabled, allowing the easy spotting of spikes, such as those occurring in the knock sensor output when detonation occurs.
The Monitor function works quite well, and is one reason why many people mount the pendant permanently on the dashboard as a multi-function instrument. Compared with buying and installing a LED or LCD intake air temp gauge, for example, using the APEXi pendant makes good sense - the sensor is already installed and no extra wiring is needed!
However, it is the Setting menu that is of greatest interest - this is the one that allows re-programming of the management maps. The following maps are able to be altered: Ignition Timing, Injector Opening Time, Airflow Meter Type, Injector Trim, Boost Pressure, Acceleration Enrichment, Ignition and Injection Correction, Cranking Enrichment, Coolant Temp Injection Correction, Rev Limit and Idle Speed. While this looks extensive, there are some notable exceptions. For example, there is no intake air temperature correction chart for the ignition timing, no deceleration enleanment control, no running (ie not just start-up) intake air temperature fuel correction control, and so on. These maps almost certainly exist in the software, but they are not accessible - at least, not via the hand-held pendant, anyway.
In addition, there are a number of other screen displays - the Etc bit! Sensor Check displays the output signal from each of the engine sensors, so that they can be seen to be working appropriately. Function Select enables some very important features - the Check Engine light can be flashed if certain parameters are exceeded or certain conditions occur. For example, it can be set to flash when detonation is detected, or the injector duty cycle is excessive. Closed loop operation (ie the oxygen sensor being used to control light load and idle mixtures) can be switched on or off. Finally, the contrast and brightness of the LCD display can be adjusted.......
Full article (with pictures) continues here
