I’ve had a Vem’s Wideband & EGT Gauge for a while now, which has worked fine as a wideband logger. I fed the RPM input into it but occasionally it keeps dropping out, intermittently which although annoying does not cause much grief in the log files.
We tried hooking up the pressure sensor signal to it, and enabling the dial in the software MegaTune – which although appears basic is incredibly flexible. It does require us to work out the calculation for the analog input. I have not finalised it yet as I may change the resistor used on the input line (the display switching button also uses the input line – a bit weird once you know). If I change it then it will affect the values and I will have to calculate all over again.
Doing the calculation is easy – I know the sensor is linear and I have the voltage:pressure calibration points, so it is just a case of calculating the input value to display something meaningful.
I also made the mistake of putting on the latest firmware (2009-04-30) – avoid this, and the previous one (2009-03-??) and stick with the firmware dated (2008-02). The latest didn’t allow the gauge to boot properly, it hung on counting up warming up the O2 sensor and displayed FF’s and FU’s. Then you can’t apply the previous firmware. The trick to get out of this was to switch on the gauge and immediately start the firmware update.