Joined: Jan 2005
Ditto to Sam above. If you do choose to "Tune" or tweek the factory computer settings, use a good quality aftermarket tuner such as the DiabloSport Predator (DSP) or the SCT Xcalibrator. I recently used the DSP with the 86 Octane Performance tune. I saw a big difference in the overall performance and smoothness of the engine. I had a bit of valve train clatter that has virtually gone away. The 4.6 Modular engine has a lot of noise from the various components in the OHC design. I knew there was a bit of slop in the factory computer settings, but was amazed at the improvement the re-tune did for drivability. There is a bit of a lag in the electronic throttle (not as noticeable in the 5 spd Man though), but there is virtually none now. Overall, I would recommend doing this.
If you are going to make any performance modifications to your car, then you will have to re-tune the computer to account for these changes. This includes any intake mods like a cold air intake, charge motion control valve plates, etc or exhaust mods like headers, free flowing exhaust systems (Borla, JBA, Magnaflow, etc), etc. Before anyone shouts Waranty issues, talk to your dealer's Service Advisor as to your their policy on after market performance parts and computer tuners. My dealer has no issues with this and they have to prove it caused a problem with your car. There is a lot written on this throughout this forum, so research it before you do it and don't take our word totally on what you should or should not do since we are making a choice for ourselves to make more of our cars.
There are a lot of improvements you can make in the new Mustang, but research it out and read this and other forums to find out what others are doing. We can help you out, but research, research, research before you do anything to your car. Many of us do know a lot and are good sources of what to do and not to do. I for one know just enough to be dangerous! Aahhh..ha...ha...ha...haaaaa....
2008 Bullitt, #0546, Black
2005 GT Coupe, Performance White