Lots of people still talk about "Megajolt lite jr" even though they mean "Megajolt" in more general terms or more specifically the more recent Megajolt V4 and Megajolt/E. Don't let this worry you. The Megajolt system has gone by a few different names over the years but they all work the same way, control the EDIS ignition exactly the same, share the same connectors and can use the same ignition maps.
In rough chronological order of their use the version names are as follows:
- Megajolt Lite Junior / Megajolt Lite Jr / MJLJ
- Megajolt V2
- Megajolt V3
- Megajolt V4
- Megajolt/E
Each version incorporated minor revisions and enhancements but Megajolt V4 (Released in 2008) onwards uses the same windows based configuration software and can be used interchangeably. Megajolt V3 and earlier use an older Java based configuration software.