It sounds like what you want is a BMEP/BSFC chart. This is the standard industry tool for measuring fuel consumption with load and RPM - it has BMEP (brake mean effective pressure - proportional to torque output) on the vertical axis and engine RPM on the horizontal, with contour lines of specific fuel consumption (g/kWh or lbs/HP*h) through it.
Originally Posted by chevy_volt00
One for the Volt was presented on Ecomodder a while back, but it popped up in a single post with no explanation for the source and some people believe their experience contradicts it. It showed up in this thread, a few post down:
For reference, your TDI is near the bottom of this page: (I had a 2003 TDI for several years myself)
C4884 - White Diamond, purchased 10/15/11