[RichMusson]

What are you running?
If it is a fairly stock engine the dyno will help getting it set right but you will not get all that much more power. I mean there just is not that much to play with to get extra power out of it.
If it's just timing and jetting the Carb on a stock motor you could probably save the dyno cost.
The dyno is not cheap. If you are on the machine a couple hours to set and reset etc. You will pay for it.