Results
The first thing we noticed was the OBD-II interface doesn't initiate communication with the car every time. We found the EGS had to be powered down and re-started a few times to initiate communication. Once initiated, we were able to cycle through several different channels of data including: rpm, boost, engine load, airflow, ignition advance, intake temperature, water temperature, etc.
On different cars, different data channels were available. We used the scan tool function to check engine codes which worked, but we didn't attempt to clear any codes. Set-up was easy and straightforward and every time we installed a new module it was instantly recognized by the EGS.
Discussion
We can't explain why certain data channels were only available on some cars. In theory, all cars should have the same channels present through OBD-II. Obviously boost won't be available on a normally aspirated car, but things like airflow and ignition advance should be available on any gas engine. The sampling rate of the EGS seems completely adequate, though it does slow down with the more channels you record. It saves to data files in folders, and once one folder is full it automatically starts a new one, so no data is lost. There is currently no way to get the data off the EGS, but there is a firewire port in back that makes us hopeful this is planned for the future.
Conclusion
It's easy to think of the EGS as just another car gadget that's fun to play with but not particularly valuable to real tuners. After a few weeks of use, we found that we started regarding it more as a tool than a toy. We still aren't sure if European car enthusiasts will be turned off by the thought of mounting what looks like a big tachometer in their cars, but they will definitely appreciate the data. To be honest, we felt a little silly driving around with the EGS mounted to our windshield, but at the same time we realize that this isn't something you would use on a daily basis. Mount it up at the track, take a few minutes to calibrate it, select the data channels you are interested in, and away you go.
Another option is to mount the system somewhere less conspicuous. Since all the modules use either ethernet cables or serial cables, the EGS unit itself can be mounted anywhere with the shift light and control module mounted within easy sight or reach of the driver. Our other concern is that data can't be taken off the EGS. It's easily viewed on the system's screen, but we would like to be able to download to a laptop for analysis.
Overall impressions are very favorable. It's so easy to use that the average driver can pick one up, plug it in and be collecting data in a couple of hours. He or she can use it to check trouble codes, check to see if the car really is producing the boost promised by aftermarket parts makers, and even get an idea of power gains. More serious tuners can log just about all the data necessary for developing anything from intake systems to turbo kits.
If you are buying an EGS, we would definitely suggest buying at least some of the accessories at the same time. A basic EGS will give you tachometer and voltage. If you have an OBD-II car, the adapter module is invaluable. If your vehicle is pre-OBD-II, you can use the ADC 8-channel module to gather whatever data you may need. This is the real advantage of G-Tech selling everything separately: buying what you need when you need it.
The looks of the system initially turned us off. But after a few weeks of use we've really come to appreciate its usefulness. Its ease of use makes it fun for the gadget lover, but its expandability and robustness make it a genuine tuner's tool.