if your asking if the stock header collector will accept a 2.5 in.exhaust flange yes it will the ball on the collector allows it accept different sizes but i'm not sure exactly how large but i have a 2.5 in exhaust on mine and previously it was 2.25 and i had no problems...
good looking out SeventyMach1 i revised it using flange and collector in the right places i just work on and drive mustangs i don't memorize all the part names lol....Mustangless are you upgrading to a 2.5 in. exhaust...by the way how do yall like my new signature picture..
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