I am pretty sure i read that there is a tune for the 3.27 loaded from the superchips tuner...however probably not for the ls7 maf.
I assume you currently do not have a tune. So basically you can do anything. Most will say get a dyno tune (if you have a reputable tuner near you). If not, then IMO, the next best thing would be rick or pat (unless you know, or know someone with knowledge of hp tuners).
Get a budget and talk to some tuners and see what they can do. I have pat, and he did my seperate tune for the ls7 maf. He, along with a few others, can remote tune for basically anything.
Current: 2009.5 SBM G8 GT, Premium Package, Sunroof, Pat G. ECM/TCM Tune, Roto-Fab 102mm CAI, LS7/LS3 MAF, Kooks 1 7/8" LT's, SOLO HFC's, SOLO Mach-Shorty Balanced Catback, SOLO 3.5" Tips, 19" Sport Package Wheels, GXP Steering Wheel, GXP Diffuser, Neondials, VG Sharkfin II, Debadged (Except Arrowheads), Hood-Vent Mod, Lower Grille Mod
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