I picked up a aftermarket exhaust manifold at the macungie pa.car show yesterday.it is called a haydees flash it has a fitting at both ends and a internal tube that terminates at these fittings.the internal tube is burnt out near the middle and a brazing repair was done near the exhaust end of the manifold.i guess i just had to have it and the price was real low,does any body have any info about it and i'm wondering what that internal tube is all about,thanks frank.