There are many threads on these sway bars, but the comments here cover the gist of it.
I’ve said many times that for an IRS-equipped vehicle, if you want to take corners tighter (i.e., more over-steer), you only need a larger rear bar and/or stiffer rear dampers. A front bar is just a waste of money. If you want to do it on the cheap, the PIU rear bar (23mm vs 21.7mm for the ST) is only $100. As also mentioned, the PIU shocks are another upgrade. I wouldn’t bother with the PIU front bar since it’s 35mm like the base model (one is hollow, one is solid), and the ST’s front bar is 34mm - the
smaller front bar being better for tighter turning.
This chart from my Cobra site sums up all the high points nicely, along with good reading at these links:
http://terminator-cobra.com/suspension.htm
http://terminator-cobra.com/chassis & steering.htm
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