nobody knows exactly what is done to the civic.
In sports compact or import tuner (cant remember) they had a few pages on the zfever r33 syline. It is mostly stock on suspension and brakes, but it is a rb26dett.
The possible power to weight difference does make a big factor. But that skyline might have been reving, but wasnt going to risk nor waste its time with the civic.
Maybe the civic is faster, maybe the r33 is, but this video proves nothing until they line up and go from a dead stop!