The Bachmann Spectrum heavyweight passenger cars have a coupler pocket that swivels with the truck movement, but they are still limited to nothing less than perhaps an 18 inch radius because of their diaphragms, unless you put an unrealistically long shanked coupler on them. We have a minimum 22 inch radius on our HO scale club layout and the Bachmann cars don't look good at all going around even that large a radius -- and neither do any other brands of passenger cars.
I need to know how low track radius cars with body mount couplers will operate on ?