If you're asking whether it's possible to install dev/py on a separate box, yes - that is a common type of implementation.
It seems as if you're asking whether you can install dv and py first and then pd at a later time. That is possible, but you might have issues. You really want to ensure that the system databases (system, data dictionary, object librarian and central objects ) are stored on the production box. Having duplicates of these results in having, in effect, two implementations - and trying to run two implementations is double the management and a lot more cause for issues (especially with regards to promotions). The better method would be to implement everything on your production server, then move dv/py over to your secondary server at a later date. Changing production server name is very nasty - but adding an additional server is not tricky at all.