I've swapped custom tune to custom tune (bama to mpt, vice versa) several times without going back to stock first. I've encountered no problems. Going from stock or back to stock seems to take soooo long compared to just switching custom tunes.
2013 DIB 3.7-Pypes Pype Bomb black axlebacks, BBK shorty headers, Bama & MPT tunes, Steeda Ultralite Springs, J&M steel adj. panhard, Roush hood scoop, Street scene Gen 2 chin spoiler painted to match, Custom billet grille, painted side mirror covers, 20" gloss black AMR wheels wrapped in Nitto Motivos.
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