Why would someone want to cast one? I see almost as many of these exhaust manifolds for sale as I see USED Fenton header sets for sale.
I know a fellow who has built several Corvettes from that era and he never used the stock exhaust manifolds because he could buy two sets of Fenton headers for the cost of a Corvette exhaust manifold. The Fenton cast iron headers do a better much job of moving the exhaust out of the head then a Corvette exhaust manifold.
Just as a side note, he would also put 261's in his built Corvettes to get a few more extra cubic inches.
I guess the thought was that every little bit helps.
Joe
