Hub thread pattern

[Dan Case]

Originally Posted by CompClassics

On the "55" stamped original production line knock-offs the "55" indicated the thread pitch. Dan made reference to a manufacturer change, it was from Harvey to Alcoa, I believe Alcoa bought Harvey.

Correct X2

As far as I know Halibrand made KOs were not stamped with 55 until 427 Cobra street car completion started. Speculation on my part is that parts for GT40 MKIIs might have been on hand by that time???? Cobra race car owners don't want the stamp while 427 Cobra owners do. Did you know that it was not rare for CSX33xx cars to be delivered with steel nuts on one side of the car and aluminum ones on the other side? (Circa 1969 Halibrand released a new steel nut with rounded ends on the wings. Guess where I see them most? On CSX33xx cars. I just cannot help but wonder if owners / dealers took the opportunity to have all four nuts on late cars the same design and material? Interesting to think about since some cars didn't get sold new until 1969. That gets to the issue of what "original" means to different people. Was "original" for many details, as cars left for delivery to a dealer or after dealer preparation for the first buyer.) Details, details....

Also GT40 MKIs converted from wire wheels have the same thread. GT40 MKII and MKIV have different threads and were normally dyed red or blue depending on direction of threads.

I have collected samples used or nos of every brass, cast steel, forged steel, and forged aluminum straight arm, forged aluminum curved arm, KO AC Cars, Shelby, Holman-Moody, FAV, or Kar Kraft used between the first street Cobras and last GT40 MKIV except the steel ones used on most 427 street Cobras. I have found some but each time a 427 Cobra owner pleaded to get “the last part” they were after. I have recorded which Cobra, 427 Cobra Comp car, MKI, MKII, and MKIV the used ones of those types came from. I have a front from a Daytona Coupe removed in 1968 but I have forgotten the chassis number and have not yet tried to figure it out again. I have a set of wire wheel nuts for a GT40 MKI but the chassis number has been lost to time.

Original wheel hubs and center lock nuts is a very complicated subject!