I can say that yes the stock bov vents on spool when I had it venting to atmosphere, I rigged up a really dodgy bent piece of metal which then bent out to vent the air, but I found that having something blocking it almost stopped the stalling on idle, I found this out by holding my hand over where the air vents and it idled smooth as silk, once I unblocked it, BAM rough idle?
I have no friggin idea what this means and am not a mechanic, I will be taking pics later on before I reattach the plumb back just to prove how DODGY it was , sick of just before boost hearing a constant whoosh from the bov and thinking of all that power being lost