I wouldnt go with the chip for exta proformance. I would get the computer programer. The chip is limited on its abilities. With the programer you can increase air to fuel mixtrue, increase /or decrease tire size and still have correct odometter and speedometer readings. Able to change cooling fan on and off switches, etc.
Have heard a lot of problems from those with the Jet chip. I would like to see a PCM tune from Wester's Garage that would remove most of the torque management and work on the retarded timing of the 4.2L. Supposedly they are close to having something.
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