To do what you are trying to accomplish could lead to political suicide if things do not work out.
It sounds like you are in intern currently looking to start at a new program in four weeks. First, have you signed your contract for next year yet? If you are not VERY politically savvy, your chair/PD could simply find some dude/dudette from APDS.org looking for a PGY-2 position to take your place, leaving you out in the cold. In order to apply for one of those open positions, two to three letters are usually required, and one of those letters usually has to come from your chair/PD.
Also, if you go to some place and do your lab time, your home program must still sponsor you (you are still under their jurisdiction). Meaning, in order to take the ABSITE they still have to report to the ACGME that you are in a training program. If you lose that sponsorship, life can be difficult.
But getting back to your original question, navysurgeon has some good advice, but I would be careful about approaching your PD and saying you are considering transferring. Often a PD does not have YOUR best interests in mind, but his/her PROGRAM'S best interest in mind... and going into the next academic year one junior resident down is not a good thing for morale, or for the schedule, or for the 80 hr work week.
Good luck 15blade.
If you want to be in an academic program closer to your family, did you interview on the west coast? Did you rank west coast programs? And for the applicants next year, what decent private community hospital on the east coast are you in currently? It sounds like you are unhappy for some reason. Correct me if I am wrong.