I will apologize up front for sounding like a "Dutch Uncle" for a moment….IMHO, going with a mail order tuneis really no different than your grandparents taking their car to"Tune-Masters" for a tune-up......yes, they did change the plugs etc,but they were not there to fine tune the car just find the middle of the roadwhere the car runs and get it out of the shop. Mail order tuners are nodifferent...anyone who claims they can tune your car without everseeing it is selling camel poop- period! They cannot tune yourengine without seeing the data specific to altitude, humidity & fuelburning characteristics- just because you use 93 octane does not mean the 93octane they used on their dyno (tuners) has the same burning characteristics...nordo they typically address the seasonal fuel blends for each region of theUS. I have a friend with a GT 5.0w/factory blower....with the aftermarket tune, blew the pistons through thepan........and he is eating the engine......Ford wanted $10k to replace.....hecalled me for advise, we have it down to about $4k for repairs with him doingmuch of the labor. Perhaps what is equally importantis the parameters that can be adjusted are set by the OEM vehicle software…sothere is really no “magic” in what they are doing anyway. If you go to this linkhttp://www.fordracingparts.com/downl...ceTechTips.pdf the engineers at Fordracing have a article on just exactly how these “tuners” play games with the hp/tqratings, how calibration can cause misleading dyno results, & some of the“tricks” that are used to gain supposed power increases when in fact,mis-managing your engine.....and the most important item is……these "mailorder tuners' are not regulated like any other auto repair shop in the US...soif they "damage" your car...gee, sorry...sue me! It is important to verify the“Tuner” is ASE certified in ECM& Trans programming & current. Plenty ofpersons advertise their programs to be the best & offer custom tunes, butvery few have credentials in these areas. Some of these “geniuses” have causeddamage to a few vehicles- just jump over to flatratetech.com & readcomments from the MSE techs!
Ok..I'm done now...…
Been saying this for years. Was told a long time ago...well almost a long time ago (2006), by one of the top tuners in the country (Ken Bjonnes) that no 2 engines are alike, therefore what Beechkid says above is very true. To get a good, almost perfect tune, it has to be done at a reputable dyno shop. Everything else is guess work.