Thanks fellas - to add to the confusion here I have taken a screenshot of Summit's listen for Sanderson Y Block headers. Welp - cannot insert a photo just yet. Here is a link that shows TWO different types of Sanderson TB Y Block headers. Ford Parts and Accessories | Summit Racing
The FTB1-P I have owned/used a set of those and they are indeed Thunderbird specific. This is a set we all know about with the collector very much near the location of a passenger car motor mount. I just swapped a set with Charlie Brown up in New York. These only worked on my run stand.
However, the other set shown, the SEC variation... when I contacted Sanderson they said they only offer one set of Thunderbird (TB) headers for the Y Block, the (P) set. The tech said that he had never heard of the SEC version. The SEC set has the collector exit much further back - maybe in the stock location. I wonder if the SEC set would work in a 55-57 passenger car? If Sanderson says they do not sell that set, but Summit is planning on having them ready by July 10 who knows? To finish this off, if the SEC set is going to be offered by Sanderson, and if indeed the collector is in the stock location, would it not be too much of a variance for them to produce a driver's side for the passenger car as well? I guess I need to find out how much the original cast iron exhaust manifolds from Thunderbird to passenger car differ.
aka "The Hot Rod Reverend"
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