Could you of overtorqued the valve cover? They get a really low ft/lb, something like 2-3.
Turbo's spool based on engine load (among other things). An unloaded engine doesn't require much air to rev, so you will not be passing much air across the turbine, so you will not build boost in neutral.
Turbo's spool based on engine load (among other things). An unloaded engine doesn't require much air to rev, so you will not be passing much air across the turbine, so you will not build boost in neutral.