Paul, just a note of explanation on your comment
torque is determined by thread size and completely independent of application.
Engineers designed these engines around what was available at the time . They would not have fitted 3/4 studs if the torque could have been much lower - they would have used thinner/cheaper/less-wasteful-on-material options.
The torque was then applied to fully utilise the clamping ability of the fixings. Simple as that.
An alternative could have been finer threads which could achieve higher clamping forces (which were not required) - and coarse threads are easier and cheaper (and less likely to get damaged?). Those engineers knew their stuff
So, no, the application was taken into account. They chose 3/4 studs for that application So it followed that the torque was 'as given'. We tend to now go round full circle, but the engineer had covered all the specification requirements on his standard list and had come up with the cheapest/easiest solution. So he stopped and moved on to next issue on his list.
If at any time he found something elsewhere that called for a different solution than that had been covered above, he would go around the above loop again to check out any changes which might be required to the design before even starting to make the item.
Complicated , but a simple procedure. Computers now look for these anomolies and flag them up on CAD systems.
i write 'he' for the engineer. Almost universally they would have been a 'he' in those days.
Regards, RAB
