Phase 1 VN Series 1's (in good working order with the original computer chip and cam-shaft) are the fastest. They are significantly faster in terms of acceleration than updated V6s - especially Ecotecs (VS onwards). They were rated at 7.8 seconds to 100km/h, and were more powerful than the all of the carburetted V8 Commodores - 20 years ago in 1988. They produced the same amount of torque at just above idle, that the VL Skyline engine did from 4,000RPM. The torque curve before torque converter changes started to happen in 1989 was flat at 92% torque produced all the way from just off idle through to about 4,000RPM.
With the stock crush bent restriction exhaust they still don't run out of puff until 90km/h.
They also don't do well in high revs - they are pretty much useless above 4,000 rpm.
In October 89 they introduced Phase 2 of Series 1 - a lower performance quieter smoother cam shaft was installed, however, ignition timing was advanced by a few degrees throughout. These new cams ran out of puff when driven hard, but were quieter, smoother, and less violent, plus the extra timing made up for the differences for many drivers.
In November 90 Series 2 came out with the same cam shaft but with a low performance mem-cal (several degrees less timing throughout).
Many VNs have mis-matched chips etc these days so you can come across even more differences between different VNs.
Another problem is that so many people just automatically assume that VNs are just weak V6s without knowing of the huge amount of complications let alone that different Phases of one series occured, let alone other changes and even the fact there is a Series 1 and 2, and so on... Things aren't so simple as 'it's a V6'...
