Rub pork with garlic, salt, and pepper. Wrap tightly with plastic wrap; chill at least 8 hours or up to 24 hours.
Unwrap pork; place on a rack in a roasting pan.
Bake at 325° for 4 hours or until a meat thermometer inserted into thickest portion registers 160°, basting occasionally with drippings in pan. Let stand 10 minutes before serving.