garrymatthews

I have a downpipe with a hi-flow cat and a straight through mid section on it's way, for fitting to my 02 wrx. I am planning to retain the Prodrive back box and wondered if anyone could give me some advice from their experience with a similar set up. I am considering investing in a "knock" sensor of some sort and would appreciate any recommendations in that area. For reference the car remains in its original state of tune in all other respects