[redmodelt]

That is not completely true. Torque was set by the length of the wrench used and where the average person could turn it till it stopped. That is why wrenches come in different lengths. The spark plug wrench when used properly yields about 45-50FPs of torque to the head bolts. Just because there may not have been torque wrenches presay, does not mean engineers did not understand torque values when making tools.