Stock, HP peak is around 5200 and TQ peak is around 4200. The TQ line drops slowly (almost flat) from 4200 and then drops off sharply with the HP at around 5200. Running to redline in stock trim doesn't do you any good.

This was on a Mustang Dyno with about 7000 miles on the car and the only mod was Flowmasters...

 

Here is my graph.. Custom Tune with mods in sig..
As you can see the TQ drops off but teh HP stays pretty flat up to about 6200 rpm.

I try to shift around 6200-6300rpm. With the stock rubber (not the 26" DR's) I would wind out 3rd gear to the 6800rpm limiter so I could cross the line with out having to shift to 4th. Now with the shorter DR I have to shift to 4th which hurts my time. I tend to shift from 3rd to 4th around 5800 now.

I need my 4.10 gears now as the 3.55's are hurting me big time now in the 1/4th

 

Bama and Brenspeed both put the limit on the Xcal2 at 6800...