Interesting thought, but based on everything that I've read (including comments in the .hdv file) the value for
z and also the '
FuelSetting' parameter should be expressed in litres. Also,
x and
y are effectively arbitrary - they can be set to anything - therefore converting from one measure to another would be performed internally since the values that would be used for conversion are constant. By looking at several cars I have found that most just have
x and
y set to 1.0, whilst only a few (including the Ferrari and McLaren) are using different values, so my guess is that they have some special significance (otherwise ASR could just simply set
z to 54, and both
x and
y to 1.0 as well).
Meanwhile, you might find this link "interesting":
http://www.ausfactor.com/rfc/HDV.htm