Thanks for the info. I also decided to live with it for a while but I'm tired of hearing it. In your case,does the sound seem to center around the cat as well? I've also thought that it was due to the way the 2 pipes were "squeezed" together to form the union to the cat. I've suspected that the knock sensor was picking this up as well,which is hurting peformance. Have you tried to have the Y pipe rebuilt? My brother and I put the exact same exhaust system on his 91 Formula(headers,cat and catback identical) but his didn't have the noise. What's your setup? Maybe there's a part other than the exhaust that could be causing this. I'm planning to change the torque converter and flexplate for 2 reasons. One to eliminate the possibility of that being the problem and two,because I've wanted a higher stall for some time now and it gives me a good excuse with the wife.Can you help any further?


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