Lionel - Running 054 Cars on O48 Curves - Part1 

This is the first part of a 2nd video coming soon. It shows how a passenger car rated for O54 FasTrack curves can actually run on 048 curves using a little trick. The min curve requirement is based on a 180 deg curve. Even higher rated curve passenger cars can run on smaller curves as long as the curve is 90 deg or less. It's the 180 deg curves that can get you. By putting a straight piece as small as 1 and 3/8th" between two 90 deg pieces of track can prevent an o54 rated passenger car from derailing. Now I wouldn't try to run something like O72 on an O48. I would limit this to within 6" radius reduction. Any more than that and a car could derail on a 90 deg curve. Plus if you get too small the overhang could hit other stuff on your layout and also make it look more fake.