Pro Tune/Self Tune

what is the difference i should expect between a professionally tune file compared to one of mine, that i try then change and repeat that process. i'm getting pretty tired of not getting it right, and was wondering if they, the pros, get it right the first time. and if thats the case then i know where i little bit of my next pay check is going.

thanks for any help

No tuner is going to get it perfect just by doing it mail-order.
But they will get you started in the right direction...and then you can further tune the car on the dyno with a wide band.
That's how I'd do it.

Thanks Dan, thats what i figured, and i'm gonna go with it

I used a mail order tune as a baseline, but it was so far off from anything decent I went back to my FORMER baseline which was MUCH better. The timing work was just too far off, so I unfortunately lost $75, oh well.

If you have a rather common setup, you will probaby do well with a tune from the net as a baseline, and play with it.