we went to Rainbow Beach for the weekend. Deliberately left the Patrol at home and took the Legnum instead so I could finally get a decent highway run! Sitting between 110 and 120kph pretty much all the way apart from the roadworks just before the Bribie exit where it was more like 30-50kph... 9.05l/100km for 453km when I filled up on the way home.
that was just driving normally - ie not worrying about keeping revs under 3000rpm or anything and nursing it along like you need to in a manual Air con on. Even gave it a few squirts a passing cars and through the twisty hilly bits going into Rainbow Beach.
In short it is a simple feedback device to the driver to indicate when he/she is driving inefficiently, using inputs from the TPS (Throttle Position Sensor) and MAP sensor. I realise that this may not be practical in a VR4 as a MAF is used instead, but the article also raises some points on efficient driving techinques. Also I cannot vouch for the effect of forced induction.
I think that there are a couple of points that can be added to the driving techniques section at the start of the thread:
1: Where possible remove your foot from the throttle completely, as the ecu will cut virtually all fuel on overrun
2: Where possible drive at a lower rpm and higher throttle percentage (within reason. ie; dont drop engine revs excessively or punch full throttle)
Referring back to the first post, there is also an article on trialing a rear undertray on a Honda Insight, with fairly marginal results.
There are a hell of a lot of good articles on this site, majority of which with data/validation to back it up, I highly recommend that you take the time to subscribe and browse through some older stuff too.