Vetteworks now manufactures exhaust collector pipe flange with 2.5" flared 3" long collector pipe & seal will mate to C5 1997 thru 2004 LS1 Corvette exhaust manifolds. They will possibly work on C6 Corvette manifolds. This is a great way to connect a exhaust to factory Corvette C5 Corvette exhaust manifolds. Flange is laser machines and is 5/16" thick. You can buy the flanges seperately.
http://www.vetteworksonline.com/catalog/index.php?cPath=94&osCsid=55801166e86378994a775effd3c8030f
Dan

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