Ok well here is the kicker, I'm really not sure how you held the brakes and checked stall speed because you should have been burning out way before you got up to it but ok. This other article may help explain things better:

The proper way to check the stall speed is to make a standing-start, abrupt, foot-to-the-floor acceleration run and note the RPM shown on the tach at the instant the vehicle begins to move. This test actually measures "flash stall", but this is usually very close to the true stall speed of the converter. Also, this test is only valid if the tires do not begin to spin and if the engine can develop sufficient torque to actually reach the rated stall speed. If the tires spin, the apparent stall speed will be high. If the engine does not develop sufficient torque for the converter, the apparent stall speed will be low.

Is it okay that I can get 2600 without spin? My TC was new in February.