There have been many a discussion on the topic of just when the power valve on the 00VI should be activated. Truth is, there is no one good point. Most of the discussion on this page was taken from a thread on the Maxima.org forums, located here.
Simply put, there is no one, solid, perfect activation point for everybody to use. This is mainly because the other modifications you have done to your car can affect what your personal optimum point is (i.e. y-pipe). The only real way to know what your optimum point is, is to do back-to-back dyno runs: one with the 00VI closed for the whole run and one with it open for the whole run. When you've done these runs, you can then look at the point on the graph where these two lines cross and that is roughly where your activation point should be.
For those that don't have the time or money to waste two dyno runs on just figuring this out, there is hope. Lucky for you, a few .org members have done a good amount of runs to determine their own personal point, and if you simply take a look at their modifications you can get a general idea of where you should be setting your activation point. The general rule of thumb is that your activation point is likely going to be between 4600 and 5200 RPM. Most tests conducted on a dyno have come in right around 5000 RPM, but again, this may not be optimal for you. The best route is to just experiment as you can.
Power Rod Removal
Although for most of us, removing the power rod would almost seem counterproductive to the reasoning behind doing the swap, for those that are hardcore into racing or would like their car to be even more biased towards highway power may take an interest to this. Discussion is taken from this thread.
Most of the talking that has occured about this modification to the manifold has occured within the 5th gen realm of things, but essentially the results are that you lose power below ~5000 RPMs but actually gain a substantial amount above that point. It's simply a tradeoff. The reason for this is that it is believed the power rod actually restricts flow to the shorter runners once the rod switches over at your set activation RPM. So the result of removing it is better airflow at higher RPMs, but with no actual "variable" element to the manifold to allow the longer runners to do their job. This is not a reccomended mod for anyone who doesn't track their car on a frequent basis.