[Dan Case]

Need to be more specific chassis wise to have a clue. You can't go by chassis number alone to guess at engine fitment as CSX2044 for example was originally fitted with a HP289 out of sequence. When any change occurred before late 1963 exact details often depended on which shop (AC, Hugus, Shelby) did the final assembly in what time frame.

Not counting the first few prototypes done one at a time there was at least three versions of "headers" by CSX2076. Pictures of the all steel tube Shelby ones are sometimes posted on The Henry Ford site. Then there were the iron manifolds and pipes supplied by AC but they had a problem. SA created a drawing to illustrate how to modify engine mount pedestals to allow the tubes to get by if required. CSX2061 is believed, based on factory notes, to the first chassis supplied by AC Cars to include iron Y exhaust manifolds, new longer Y down pipes, and piping back to mufflers from AC Cars during chassis shipment. It is believed this was the introduction of the new long down pipes that did not require trimming of engine mount stands on the chassis. If this was the long down pipes introduction then the long Y down pipes were then used for all stock street cars from that point on.


Very early iron Y manifolds had the AC Cars engineering number cast into them. Most were not marked in any way.


CSX2034 and CSX2055 when pulled from decades of storage had the second style system just as reference points.