These cars are a blend of SD and MAF (and I would fire any tuner that turns off SD on your car - the Vengeance guy is known for turning off SD - just sloppy and lazy to do that). You can do all the low speed / non-PE (Power Enrichment) tuning based on ST and LT fuel Trims.. Remind me of your mods again - as I recall, you really didn't do anything significant (yet), so at this point, you shouldn't need to mess with it (unless you are after "free" HP, a.k.a. leaning out the factory tune) - I can say I am against that in principle.. I like to make the air pump more efficient, then simply tune the car to the same approx. A/F the factory used (only now with more air flowing through, hence more HP and Tq).