Is your 1 1/2 pound pork loin a tenderloin? If so, what I would do is remove everything else from the oven (just for 15 minutes), crank up the heat to 450º and place the pork in there (baste it if you have it). Cook 15 minutes, turn the heat back down to 350º, turn the pork over and cook another 15 minutes. When that 15 minutes is up, turn it over for the last time and cook another 15 minutes - DONE!. I always cook my tenderloin 45 minutes and it works perfectly. The 450º temperature seals the juices into the pork so it doesn't dry out. I do that when I make my BBQ Pork for a Chinese meal. The pork is very moist and nice and soft. Be sure to let the meat sit under a tent of aluminum foil when you remove it from the oven to reabsorb the juices.
Hope that helps.
