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Slight exhaust leak after restrictor plate change out

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New Boss 302 LS owner
Hey guys, just finished installing my 3/4" exhaust plates and one side has a very slight leak. This is after I removed the plates and shims and cleaned them up with a power wire brush on all sides. Reinstalled and tightened everything up and one side leaks and the other doesn't. So I wondered if others experienced this and what they did to eliminate the leak. I'll go for a drive in a bit and see if the heat expands the parts and closes off the leak as the metal expands. Any thing I might have missed? Thanks!


Because racecar.
Arizona, USA
Make sure the sidepipe flange didn't rotate as you tightened it down causing the tubes to become misaligned. Make sure you re-use all the flimsy crush gaskets.


New Boss 302 LS owner
Reply to my own post.......... Went for a drive and the exhaust sound is intoxicating! Wow, I want to drive it even more now. The leak went away after it got warm. Guess I'll keep watch on it. Nothing to worry about for sure. 8)


New Boss 302 LS owner
Thanks AZ, I did make sure to reuse the thin plates and they were aligned perfectly. I think the noise is gone. DOn't really here the ticking of a exhaust leak anymore.


New Boss 302 LS owner
Thats for sure! The car is louder now with the 3/4 plate in there, might just experiment with 1/2 then maybe none. Got the change out down pat now. 8)
Installed elect. cutouts on side pipes -- can adjust sound to what I like any time! Wide open is the best, but have to use restraint when "revenue enhancers" are present! 8)

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