Quote:
Originally Posted by yostumpy
thanks for the graph , can't pretend to understand it tho', what are the small numbers on the graph ie 197 & 210. the left side is that turbo pressure? ie at full chat it uses 197 thinggies, and at .5 bar it uses 230 of them all at about 15001800 rpm? also what are the dotted orange lines, pleaese explain to an idiot

Hi yostumpy,
To expand on what jakobnev said. I've annotated the graph.
This isn't your engine, obviously, but your Rover's graph might look about the same.
The orange arcs are approximately constant power curves. The top curve is about 30 kW.
The left scale  bmep, stands for brake mean effective pressure  is the pressure in the cylinder pushing on the piston that can be used to move the car. 1 Bar is 100 kPa.
The little numbers are the efficiency given in grams of Diesel fuel per kW hr. Lower numbers = less fuel is better. The curvy lines that go through the numbers are the points with that efficiency.
mort