This reproduction steering gear box is for manual steering cars and has a 16:1 ratio, it also has a 1 inch sector short shaft for the Pitman arm.
*The SMB-C was known for breaking sector shafts. There was a factory recall on the SMB-C and they were replaced by the SMB-D.
If you are trying to identify the proper steering box, the box will have a raised casting number of C7ZR-3550-A. The early (prior to approximately 5-1-1967, 01E date on the data plate) steering boxes (both manual steering and power steering) will all have used a 1 inch sector shaft, this in turn corresponds to a Pitman arm with the 1 inch hole. Later boxes all had a 1-1/8" sector shaft and corresponding pitman arms for manual and power steering.
The 16:1 ratio SMB-F box was used for production purposes on those Cougars with the Competition Handling Packages. The SMB-K box (same 16:1 ratio - Power Steering) is identical without a pitman arm. We at WCCC believe that the pitman arms were pre-installed on the steering boxes for use on the assembly line. That is why they have the SMB-F tag number. For those with manual steering and contemplating going to the faster steering box, 4-5/8 turns lock to lock to quicker 3-3/4 turns lock to lock. Understand that there will be more effort involved in turning the steering wheel.
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