Tuned means re-flashing the PCM, or computer, to accommodate different modifications to your car, or to improve it's performance. it can change a wide variety of parameters, the idle speed of your car, speed and rev limiters, your car's air to fuel ratio, the throttle response when pressing the accelerator, minimum octane requirement (you can tune your car for optimum performance on 93, or in race applications, higher octane fuel. when doing this, using a lower octane will cause a knock or ping, like in a a diesel engine) and multiple engine patterns to increase an engines efficiency and overall output. If you have an automatic transmission, the tune can also control the shift points and firmness of the shifts, because they are controlled by your computer as well. In earlier Mustangs tunes were beneficial for small modifications and required for larger mods, and usually done with dyno tuning or by placing a chip inside the actual PCM. In S197 Mustangs, the computer plays such a huge role that even with most small mods, you must reflash the computer, using one of the methods mentioned before, or with a handhelf tuning device such as the SCT X3 or Diablosport Predator. By simply plugging the device into your OBDII port below your steering wheel, you can upload preset tunes or tunes custom made for your car and your mods, by any of the numerous specialty tuning shops. Bamachips, Tillman Speed, and Brenspeed tend to be the big three.
Overall tuning is one of the first steps to changing your car into what it should be. The Mustangs from the factory are, in my opinion, too tame. With 4 simple additions, exhaust, cold air intake, steeper rear gears and a custom tune, the beast within can be unleashed.
__________________ His: 2008 4.0L V6 Deluxe Performance White auto, Dark Charcoal leather takeoffs, Flowmaster AT, JLT CAI, SCT X3, Bamachips 93 Race tune, Roush hood scoop, Roush spoiler, GT500 chin spoiler, 18" GT500 wheels, Eagle F1s
Hers: 2002 3.8L V6 Tropic Green auto, Medium Parchment cloth, BBK CAI, SCT X3, Bamachips 87 Perf tune | 
