With the carchip EX, you can do lots more stuff as well.
"With CarChipE/X, though, you'll also be able to monitor any four out of 23 user-selectable engine parameters, including:
RPM
Throttle position
Engine load
Fuel pressure
Fuel system status
Short- and long-term-fuel trim
Battery voltage
Timing advance
Coolant temperature
Air flow rate
Intake air temperature
Intake manifold pressure
Oxygen sensor voltage "