Every marker is different. If you want to sweet-spot your dwell, you need air some quality fresh paint, use a quality battery preferbly new or one with plenty of life and a chrono.
Clean and lube your marker (normal maintenance, refer to your manual)
Set your LPR to how you want it.
Stock dwell for an 07 is 16ms if i can remember right, so thats a good number to start.
Now set your FPS (velocity) over the chrono to say 280 fps.
* Shoot 20 balls, one at a time, make note of FPS. Average all of the 20 numbers.
Turn down the dwell by 0.5 ms and repeat above * shooting another 20 and take the average.
Repeat above * until the average FPS drops , then turn the dwell back up by 0.5 ms.