I envy you, guys.
Mine does 18mpg, combined.
On the highway does no more than 24.
In my country all fuel are E20 93oct and the addition of 20% ethanol contributes for low mpg. I usually run 50% 93oct and 50% 100oct.
ZX4 D20, mods are:
SWR Cams 280/280 degree 0.380/0.380
SCT tune (Tom)
Also I have a close ratio gear box (FD 4.06 and 0.88 5th).