Ok, so I recently installed an STi catback on my '05 Outback Sport, and am having a little trouble from under the car. First, I am using the following adapter to get the catback to mate to my catpipe because the flanges are different sizes, the midpipe is short, and the flange is rotated: http://www.rs25.com/forums/f14/t132823-ms3-exhaust-adapters-group-buy-ii.html This adapter is flat on both ends but the cat pipe's donut gasket extension sits just inside the adapter allowing the flanges to meet flat. This is where the leak is - the adapter -> catback connection is fine. I've got a flat gasket here and have it tightened down but I'm still getting a leak near one of the bolts. I tried a new gasket with no luck. Should I try to double up on them or can I use high-temp (red) RTV? If I do, should I add it to the gasket or replace the gasket? Next, I have a nasty heat shield rattle coming from under the car. I think there's two actually. My headers or catpipe shields sound like they're rattling, a little bit at idle, and a lot at around 3k as I come off the accel. The other is the midpipe resonator shield, and that whole pipe is visibly shaking under the car at idle. Would Kartboy or Paranoid Fabrication urethane hangers help the latter? Any fixes for the headers/catpipe? Thanks ahead of time for any suggestions!
I've used gasket cork before (you can buy rolls of it at autozone) to help seal up stubborn exhaust leaks like yours. Its not the best fix in the world, but it usually works. As far as the rattle, I don't know what to tell you. I would have to get under the car and take a look at it. I don't mind checking it out for you. I'll PM you my number