"...at this speed, the length of the engine had grown 6 inches and its diameter by 2.5."
Who needs Viagra? Just go hypersonic!
"What I find amazing is that, depending on which source you read, the amount of thrust being generated by the inlet at M=3.2 was between 54-80% of the total".
Shades of the "do winglets develop thrust" debate? But I guess what we're saying here is that a massive proportion of the compression actually took place ahead of the face of the first compressor, within the external shock system around the shock cone.
[Bizarrely, J58 was a remarkably quiet intake a low speeds, I seem to remember - so much so that NASA spent money trying to understand why some years ago].