I would do CAI/Tuner, following that I would go a bolt on muffler, the stock one is very restrictive. Heres a list of some of the top tuners...
CAI/Tuner Combo
• Doug/Bamachips: XCAL2 and your choice of TI or C&L CAI. (When I switched to his tune for my old TI, it shaved off 3/10ths on my time, his daily driver is an auto as well, though I think he has several test mules/test customer cars at his disposal)
• Evolution: XCAL2 and C&L (lot of guys use them, they have a good rep, actually met them at FFW, good bunch of guys)
• AZDynoChip: XCAL2 and ? (don't know if they do the internet thing, they will tune any CAI and produce some of the highest dyno numbers)
• Lidio/Alternative Auto: XCAL2 and CAI (I did some research and several shops referred me to him for Automatics, his personal daily driver is an auto)
• Brenspeed: XCAL2 and C&L (another highly reputable shop)
• Justin/VMP Tuning: XCAL2 and ? (Considered one of the top dogs for the V6 stang community, he’s also tested more CAI’s on the same dyno session than anyone I’ve seen so far, read about it here:
http://www.v6power.net/vb/showthread.php?t=25551 )
Stick with any of the above and you will be fine.
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Best 1/4: 10.97@122.09, 1.56 60ft w/4.0 V6
Best 1/4: 11.67@115.45, 1.64 60ft w/5.4 3V
Best 1/8: 7.401@92.77, 1.65 60ft w/5.4 3V
www.rygen.net/stang