Entry Level ECUs

These ECUs run open loop fuel control, meaning that they use no feedback for fuel control. This makes them unsuitable for road use (with the exception of the UniChip, as it retains the original factory closed-loop ECU), but are fine for track cars, off-road recreational vehicles, boats etc.

UniChip

The UniChip is a bit of a misnomer, because it isn't a power chip at all, it's actually a piggyback ECU. These connect in parallel with the original ECU and modify the fueling and ignition timing as instructed. This of course relies on the original ECU being available and mostly working (eg, if you change cam profile). Because the factory ECU relies on the factory sensors, if the factory ECU used an air flow meter, this must be retained.

EMS

EMS have just released a new range of two budget ECUs; the 8860 and the Stinger.

Microtech

A few models and accessories available. Unlike most other manufacturers, they have price listings. They also have downloadable wiring diagrams for different applications.

Microtech will be releasing a new range of ECUs in January.

Closed Loop ECUs

These ECUs run closed loop fuel control, meaning that feedback from the EGO (exhaust gas oxygen) sensor is used to regulate the fuel amount. This correction to the fuel amount is not persistent - ie the fuel map is not corrected itself; instead a correction is applied to the fuel map.

Haltech

Another ECU manufacturer, with six ECUs on their website. Many of these run closed loop fuel control, however some Haltech's don't appear to.

Wolf

Now up to version 4.4, the Wolf 3D also is available in a "plug-in" type, which are suited to specific engines, and save on installation time as there is no wiring to be done. The Wolf 3D ECU runs closed loop fuel control.

Hawk

Another generic closed-loop ECU.

Closed Loop with Adaptive Fuel Control

These ECUs below have some form of adaptive fuel control. The difference between these and simple closed-loop control is that the fuel correction is integrated back into the fuel map, allowing automatic tuning of the engine, provided the operator holds the engine conditions steady.

Link

Link offer stand-alone ECUs as well as boards that replace the factory board inside the original enclosure. The factory replacement ECUs are limited to specific vehicles. With a separate tuning module, some Link ECUs can offer adaptive tuning similar to the Motec.

Autronic

A higher level ECU, available as stand-alone or as a replacement board for Mitsubishi or Subaru vehicles.  They have an "Autotune" (TM) feature, which is the adaptive fuel tuning mode, however this is extra in cost. This is a true "hands-off" tuning mode, as with the Adaptronic. The Autronic uses slightly different tuning parameters to other ECUs - most store the desired fuel injector duration in milliseconds, whereas the Autronic stores a VE table. This means that you can select a different injector type or target air-fuel ratio without needing to retune the engine.

Motec

These are probably the best known programmable ECU. Very flexible and fairly generously featured, including 512kB of datalogging and versatile crank angle sensor options. Those in the know say they are the best around, but expensive. They have a "Quick Lamba" feature, which is similar to the adaptive fuel control of the Adaptronic, however not intended for continuous use and must be activated via a laptop, as far as can be interpreted from the user manual.