Whats the difference in tunes?

[Jon Roseman]

I have an 06' 5.4L with aero 3030 exhaust, 3 in leveling kit, AF1 CAI. I was wondering what the custom tunes do exactly? Are they just messing with the setting I can customize on my performance setting already or are they more advanced than that? Either way I don't know enough about it to customize my own as far as timing, shift firmness, etc. Also, I wanted to know if anyone has any advice as far as making my own setting on performance canned tune. Bill, I will be requesting some custom tunes either way but just wanted some information.

I would appreciate any help!

thanks,
Jon