The B-47 has six underwing GE TG-190 engines, two on each inboard pylon and one on each outboard pylon.
The inboard engines are mounted on a long pylon that extends well below and forward of the wing, such that the inboard-engine tailpipes are (longitudinally) just about even with the wing’s leading edge.
The outboard engines, in contrast, are mounted on much shorter pylons and fit snugly against the underside of the wing, with their tailpipes extending aft of the wing’s trailing edge; they’re placed so far back that their pylons even protrude beyond the trailing edge.
(Image originally by the United States Department of Defense, via Balcer at Wikimedia Commons; modified by me.)
Why the long pylons and forward mounting for the inboard engines, versus the short pylons and rearward mounting for the outboards?