Using CMR for custom tuning

[VinnyVette]

I have a 2001 Corvette M6 with minor aftermarket bolt-ons. These bolt-ons consist of Donalson Blackwing Airbox, Granatelli MAF sensor, Borla Stinger Exhaust w/x-pipe, etc. I have three questions. 1.) If I use a CMR for custom tuning, do I just tell them the list of my bolt-ons and they create a custom tune for me to save to the Predator or is it only based on a live dyno session and they use the Predator to adjust the parameters to the most optimum performance? 2.) Is the Performance Tune that is already programed into the Predator just set to optimize a stock car with no aftermarket bolt-ons? 3.) After installing my Granatelli MAF sensor, it made my air/fuel ratio lean. I had to take the MAF off and put back the stock MAF. Can the Predator adjust the air/fuel ratio to safely use the Granatelli MAF sensor so I don't end up wasting $350 on the Granatelli MAF sensor?

[johan]

For those mods (aside from the maf) you do not really need a custom tune, i would just dial your fuel trims in and you should be good with the regular Predator tune.
Now to the maf, what a tuner would do to fix your lean condition adjust your maf curve so your trims would be back to stock thus negating the whole purpose of the maf leaning the vehicle out, you will be better off with the stock maf once you put a tune in the vehicle. Those maf's are good for vehicles with stock pcm tuning but once the pcm's fuel curve is leaned out adding the additional leaning out via the maf usually causes a too lean condition.