Tesla Electronics has made a name for itself with the G-Tech Pro accelerometer that is a portable, in-cockpit unit that reads out acceleration and can give you, among a raft of things, quarter-mile e.t. and speed readings that are very accurate. At the ’07 SEMA show, Tesla introduced the Expandable Gauge System (EGS) tachometer. At first, I thought this was just another gimmick tachometer, but after installing one in my Chevelle, I quickly realized how much I’ve come to like this piece of equipment. As the name implies, the tach allows you to expand on the tachometer feature to keep track of additional information like wide-band air/fuel ratio, fuel pressure, water/oil/trans temperature, and a whole host of other things. If you wanted to electronically monitor fuel pressure, for example, all you’d need is a pressure transducer that will convert line pressure into a 0- to 5-volt scale that can be converted into a psi reading on the tach. Making this information even more power is that the Tesla EGS tach is designed to data-log any information fed into it. Air/fuel ratio information is gathered by adapting an Innovate wide-band oxygen sensor system into the tach so you can display the information in real time and data-log it for later reference. I recently used this feature at the dragstrip to look at the air/fuel ratio during the entire run and discovered the engine was running way too lean at the top end, requiring more than just a jet change to the carburetor to stabilize the air/fuel ratio. I’ve also used the real-time air/fuel ratio information to help tune the part-throttle to improve driveability and fuel mileage. The tach lists for $299.95. If you want more information, check out Tesla’s website at gtechpro.com.