On 5 Mar 2006 09:38:55 -0800, "Dr.John" wrote:

I'm adding a room in a basement and running a couple of new circuits.
Since the electrical boxes are a trivial expense compared to everything
else, I have purchased the largest capacity boxes to use for all my
outlet and switch connections, rather than buying smaller capacity
boxes where I have only a couple of connections to save a dime.

I have assumed it is against code to have a box that is too small, but
fine to have one that is larger than required. Is this in fact the
case?

Perfectly legal.
If you want, you can have a box custom made that you can part you car
in, as long as the wires are enclosed inside. (Of course if you plan
to park in there, you'll have to put a smaller box inside )