Tim and Paul,
The PE's special brake rigging was designed so the cars could go around a 45-foot radius curve. Not all PE cars had this feature, but a surprising number did. In fact, there were at least 1,300 such cars, maybe as many as 1,900. It appears the brake rigging was applied to cars built in the 1920s, and I know of no evidence for its use on earlier cars, except possibly Hart ballast gondolas (see below).
PE 5900-5999, 6000-6099, and 20000-20599; G-50-9 GS gondolas delivered in 1923 and 1924 (800 cars). The feature seems to be invisible on these cars and may not be the same arrangement as on boxcars and flats.
PE 2614-3673; F-50-8 40' flat cars delivered in 1923 (150 cars).
PE 30000-30149; F-50-9 40' flat cars delivered in 1924 (150 cars). (Some of the Arrowhead tank cars converted from flat cars may have had the feature as well).
PE 2700-2899; B-40-13 40' SS boxcars delivered in 1924 (200 cars).
Possibly PE 10000-10599; B-40-14 SS boxcars delivered in 1924 (600 cars).
In the rosters in Tony Thompson's epic books, all but the boxcars are called out with the special brake rigging. He mentions the B-40-13s as having this in a photo cutline (on a survivor at the OREM, but seem to recall they had several when I was last there in the 1975). I saw nothing about PE B-40-14s being so equipped. The PE-40-14 photos in his book are all taken from the wrong side or end to show this, as it can only be seen clearly in a photo that shows the truck on the corner closest to the brake wheel. Ira Swett's CARS OF PACIFIC ELECTRIC V. 3 does not mention the special brake rigging at all, and the few photos there are too small and grainy to tell. Martin Loftin's instructions for his kits imply, but don't state clearly, that both classes had them on the PE. Maybe Tony would like to chime in on this
It also seems that PE 6200-6249, W-50-3 40' Hart ballast cars also had something similar to this feature, but that may have had more to do with the outside hung K-brake cylinders on the heavily trussed underframes.
Garth Groff 🦆