wierd power steering issue

I just got my new engine running. I noticed whenever I start the car with the wheels up or on the floor the steering turns to the right by itself. I don't feel any resistance holding the wheel. I have a Saginaw type of power steering pump that came with my march performance system. The steering box came from advance auto parts. The car isn't aligned yet and all the front end parts are new. Im thinking maybe because alignment is off might be causing the steering to be biased right. Any thoughts or suggestions would be appreciated.