Your shot of the engine block demonstrates the camera/lens combo is VERY sharp.
If it was me, I'd set your in-camera sharpness setting to 6, and leave it there.
The D7000 is a 16mp camera, and it's resolution is phenomenal, if the other variables are sound -- lens/camera settings, technique...
Assuming the camera, or lens, is not missing focus, or the technique isn't deficient, the D7000 will yield tack sharp images, bar none.
Nikon factory sets the in-camera sharpening very conservatively at 3, assuming perhaps an owner who likes to add significant sharpening only in post-processing, not in the camera. This philosophy may differ from Canon's, but comparing apples to apples, in a number of areas, (acuity and dynamic range) your camera is at least as capable as anything Canon makes.