There are small tolerances in the length dimensions on the 3/4” length which are no problem. For Model A purposes, the Snyder stud will work but it is a poor choice. That stud was made with the whole body at the correct size for thread rolling, which is smaller and has to be smaller than 7/16” for the metal to be displaced and come out to 7/16” on the threads.
Unlike correctly made Model A studs, that shoulder will allow more lateral movement between the gasket and the stud, which is not good. Since the Model A does not have precision dowel pins like a more modern engine, the head and gasket must rely on the clearance between the stud hole in the head and the gasket and the stud for alignment. The Snyder stud is cheaper to make, as the studs made more like the original Ford studs are extruded to allow only the threaded area to be the correct size for rolling, with the remaining size at 7/16” in the unthreaded area. On ARP studs that is the whole unthreaded area, and on the original Ford stud it is an inch, which is plenty.
ARP studs are great studs, but they are overkill for a Model A in my opinion. To have the best results with ARP, their lube [ARP Ultra-Torque] needs to be used and with their lube being used, the correct amount of reduction in torque must be determined. That would take considerable testing and analysis with a Model A and its thick yieldable gasket to have reliability and no blow-outs. In addition, I could see how the block threads in a Model A could be adversely affected, with a straight pull or axial load, with an ARP stud and their lube on the NUT thread end if the torque was a little too high. It is also my understanding that the nice looking black finish on ARP fasteners needs THEIR lube to properly overcome the friction with their fancy finish.
So in my opinion, the best choice for a Model A requiring torque greater than 55 pounds is a plain steel finish, good Grade 8 stud with at least a small shoulder (unthreaded area) at a full 7/16” diameter at the gasket area and a little above and lubed with some gear oils, as they won’t squeeze out, but motor oil still works well and everybody has it. Plus, reliable torque amounts that have been proven for many years.
