Well, you've got the PRP setup and if you add two wires to the ECM plug at the correct pinout specified by the manual you can at least test to see if it is available to be turned on.
I'm pretty sure that the capability will be there because it would cost too much to just pull it out for a couple of cars I'd think. If not, get an SVT PCM and convert your harness to it if you can get one cheaply and easily.
Otherwise use the external knock sensor system.
Former owner of '99 CSVT - Silver #222/2760
356/334 wHP/TQ at 10psi on pump gas!
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'05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red
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