i did when i was at the drag strip i was tring to knock my times down so advanced my timing a little more .5 high and low end and riched the top end up 1 percent and it took off a good tenth or 2....was running 14.15's and went to 14.0's then down to 13.9
People keep wanting to add fuel, this is not the way to go (most of the time). I used my predator on a dyno and actually trimmed 4 to 6% to get a good A/F ratio.
The timing you can adjust yourself, just keep adding more and more until you get detonation, then back off 1 or 2%