where does the pipe at the bottom of the boost controller go?

Boost Solenoid Plumbing

my mate thinks it goes to the airbox, but ive got a cone filter, can this cause a missfire under boost if it's vented to atmosphere?

 

It's okay for that bottom BCS pipe to vent to air. It's just a port for the wasted air for when the BCS is duty cycling. Subaru thought it'd be a good idea to recirc it back into the intake system, which is fair enough thinking... But it's not necessary.

 

misfire under boost is probably coilpacks..

 

its a straw it goes in you glass of milk

 

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