3.8 Litre (Ecotec) Commodore VS
Commodore VT
Commodore VX
Commodore VY
Statesman VS
Statesman WH
Then there is the regular 3.8...
3.8 Litre Commodore VN
Commodore VP
Commodore VR
Statesman VQ
Statesman VR
The commodore VT, VX, VY came supercharged so I'm guessing Holdens ecotec 3.8L is meaning supercharged.
There may be no differences between the n/a 3.8l and s/c 3.8l versions, sometimes they mark up prices on that stuff and the n/a version is always cheaper, like head gaskets.