Ok so you have a clue. I like that!
The spring mod just holds more boost in the WGA, but with these cars you do need to keep track of your boost. And without a Stage1 upgrade or another aftermarket tuner you are going to throw overboost codes.. The Stock PCM likes the tune it has and will do what it has to, to keep it that way.
My mantra:
First gauges= so you know what is going on
then start tweaking suspension/brakes= so you can handle what is going happen
then start adding power= pull it all together.
These cars can be made into wonderful little sleeper cars, you can kick a lot of the smaller stuff out there and scare the bigger stuff where they think since they didn't kick your butt easy that something is wrong with their car-The best part of a modded PT..
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The silver 03 GT is gone, but a Solstice has arrived. There are three more PT's to play with though
My personal thanks to veteran and novice crewbies that have offered information and how-to's they have been instrumental in taking LiquidPT from modded car to stock to live a more quiet and sedate life.