The Bachmann stock car is great for modification as it is the only make where the floor can be detached from the body.
My layout has terrible inclines so although I use multi-headed locos or 'helper loco' trains, I do like the sight of lone steam loco pulling a good string of cars.
I needed to find a way of somehow giving the solitary loco some help.
The Bachmann stock car came to the rescue. I would 'motorise' three or four of them. and having a removable floor would help this greatly.
Cutting a long story short (I did post threads about it on the forum some years ago but the photos have disappeared from the thread over the timespan ), I used Aristocraft centre-cab loco motor blocks with a wheel base pretty dead on for the stockcar bogie. I used one block per car and pickup axles on the non-motorised bogie.
Once the blocks were in and the cars had the Bachmann name and info boards whipped off and replaced with customised ones, they were embellished with metal detailing parts and given a weather job.
They also had a QSI 'Live action' cow sound card installed in each car.
The 'motor' stock cars worked really well as the speed of the centre-cab blocks closely matched that of the modified Bachmann Annies or single GP30, GP9, NW2 diesels that would be used with them.
I now had a lone loco pulling a decent string of cars up the inclines using the 'invisibly motorised stockcars as helpers.
The motorised stock cars also helped to 'retard' on the down gradient as well (stopping the concertina effect from the force of the cars down the slope).
I added DCC decoders to the motorised stockcars so that they could be used on digital or analogue layouts (they were given the same address as the loco that they would be working with).
View attachment 279045
View attachment 279044
In this photo you can see some 'flying' grey wires which I was part of an experiment to electrically connect the cars to each other, I abandoned the idea soon after the photo was taken.
View attachment 279042