53 plate wrx running a sti 8 complete engine running wrx ecu, 340bhp 1.4bar[avcs not wired up]how does a boost solenoid work + what are the benifits of fitting a 3 port solenoid.hearing a constant ticking/clicking noise on full boost,was wondering if the solinoid opens and closes constantly to control the boost.any advise welcome.thanks alot guys.

 

The boost solenoid works by bleeding air from the pipe between the compressor turbine housing and the actuator. It is connected by a T-piece to the pipe then the second port vents into the intake pipe. A three port boost solenoid is connected one port from the compresor turbine, the second is connected to the actuator and the third vents, this gives a much better control of the boost over a two port.
Yes the opening and closing of the solenoid controls boost by blding the air.

 

so would a 3porter get rid of that annoying clicking noise??????????

 

No, may well make it more noticeable, depending on which solenoid you choose. As 360ste says, the solenoid switches on and off very rapidly to control the amount of air reaching the wastegate actuator. A three port still does that, and some of them (the Prodrive/Pierburg one, for example) are louder than the OE two port.

 

so is it normal/harmless to have this ticking/clicking noise,had the wrx engine running same boost/power and never notice it before.thanks alot guys.

 

It's clearly not possible for us to tell you what's causing your noise without hearing it at first hand. If the clicking you're hearing is the boost control solenoid, then yes, it's normal/harmless. However, if you didn't notice it before, is it possible that you're hearing something else. You're going to need a first hand opinion to get to the bottom of that one.