Since you only have an off road pipe, you do not need a dyno tune.
Basically if you run on the dyno, your A/F. HP and TK and charted. A chip can change your A/F, your timing and adjust for a set of gears.
Once you have really started altering your engine, headwork, cams, etc, a dyno tune can pay off. For now, just get a dyno run with air/fuel readings.
A dyno tune for you at this point would be a waste of money b/c it can run $400-$500 dollars.