The WEGO III is a stand-alone unit with built-in data logging intended for harsh environments:

· Complete air/fuel ratio display system with built-in data logging. Includes WEGO III unit shown above, Bosch LSU4.2 5-wire wide-band oxygen sensor, 18×1.5mm weld nut for mounting sensor on exhaust pipe, and software on CDROM

· Versatile tuning aid for all carbureted and fuel injected engines displays air/fuel ratio (AFR) and logs over 2 hours data including AFR, engine RPM, and a spare 0-5V analog input for sensors such as throttle position or manifold pressure

· Can be used for on-road or dyno testing

· Suitable for motorcycle, and other small engine applications

· Highly accurate with less than ±0.10 AFR error over 10.3 – 19.5 AFR range

· Easy free-air calibration procedure corrects for sensor aging effects

· 0-5V analog AFR output for interface to dyno instrumentation

· Ultra-bright daylight readable blue LED display with automatic dimming under low light conditions

· Wide supply voltage range from 11-16V allows operation from battery on small engines or race vehicles without an alternator. Current draw is approx. 1 amp

· Built-in USB interface

· Fully encapsulated with water-proof LED display· Compact size: 4″L x 2″W x 0.5″H

The WEGO III is a third generation product that utilizes the proven Bosch LSU 4.2 wide-band exhaust gas oxygen sensor.

By utilizing miniature surface mount electronics technology, digital signal processing techniques, and a switching power supply for the sensor heater, the WEGO III provides the same level of accuracy as lab systems costing thousands of dollars.

All WEGO systems provide quick and easy at-a-glance verification and adjustment of the sensor free-air calibration. This allows the WEGO to maintain  accuracy as the sensor ages and maximizes sensor life in racing applications where the sensor may be exposed to leaded fuels.

Data Logging Software

The WEGO III features data logging and includes a built-in USB interface for easy connection to newer laptop PCs. This data logging capability greatly facilitates engine tuning and diagnosis of driveability issues. The WEGO III starts logging data once the sensors have warmed up (typically 15 seconds) and stores the last 8000 samples in non-volatile memory. This allows storage ranging from 13 minutes at 10 samples/second to over 2 hours at 1 sample/second. You can use our WEGO Log software to download and display this data on a chart recorder type screen. Available data includes air/fuel ratio (AFR), RPM, and a 0-5V analog input.  The RPM input can be connected to a tachometer signal or directly driven from an ignition coil. RPM data is correctly scaled and displayed for 1-12 cylinder engines. The analog input can be connected to sensors such as throttle position or manifold pressure. Analog data can be scaled to display the correct units, such as percent throttle position or In-Hg manifold pressure.

The data logging software, WEGO Log, runs under Microsoft Windows XP/Vista/7. We no longer support older Windows versions. Minimum PC requirement is a 300 MHz Pentium with super VGA display (SVGA with 1024 x 768 pixel resolution). The WEGO III connects to the PC by means of a USB interface. A USB cable is supplied with the unit. The PC must have a free USB port. If you have an older PC without USB capability, you cannot use the WEGO III. For more detailed product information, we suggest that you download the WEGO Log software an instructions. The software download includes a sample file with actual data.

AFR Data Analysis

AFR (air/fuel ratio) table display is only possible when both engine RPM and correctly scaled throttle position sensor (TPS) data has been logged from a fuel injected vehicle. The table format is intended to match the RPM rows and TPS columns used by many industry standard engine mapping systems. The figure below shows logged AFR data.

You can also display and print out the required fuel correction (in percent) based on the AFR target value you select. You can add data from an unlimited number of files that you previously saved. The data will be analyzed and incorporated into the table. Cells that vary more than ±0.5 AFR from the command value are shaded blue for rich or red for lean.

You can use two approaches to make the required corrections in the your engine mapping software. If you have Microsoft Office with Excel, you can directly copy and paste data from the WEGO software to an Excel spreadsheet and then copy and paste from the Excel spreadsheet into the engine mapping software. In the WEGO software, you can select a range of cells with the mouse and right click to bring up a copy menu. You can also left click on the upper left legend cell to select the entire table and then right click to bring up the copy menu. For more details on using Excel, including sample spreadsheets, please visit the WEGO Tech FAQ. Alternately, you can manually enter the required corrections in your engine mapping software by referring to the printed fuel percent correction table and marking off cells as you edit them. For more details, please download and read the WEGO Log instructions.