Ok I was removing vac lines that go from the turbo outlet to the wastaegate actuator and inside I found a small brass "pill".

What is it and what does it do?
Must it be replaced when I get my Stage 3 BNR upgrade installed?

 

That's not stock. Adding a restriction like that will help bring boost up faster, but too much restriction will cause boost to overshoot. What's your boost behaviour like now? You could leave it out to see how much effect it has and whether you prefer it in or out.

 

Thanks NZ for the reply.
My car is an 88 T2 (S4). I picked up this S5 turbo and manifold as an upgrade. My plan is to send the S5 turbo to BNR for either stage 2 or 3 upgrading.
Any input on that is welcome. The car has RacingBeat turbo back exhaust, fuel cut defender, K and N cone filter and FD fuel pump. I have a pair of 696cc primary and a 724cc/728cc secondary injectors. (actual flow rates per Witchhunter) I have a fresh built Megasquirt 1 which will go in controlling fuel and spark. (the FCD will come out)
I don`t have plans to go to a front mount IC anytime soon (I like my A/C)
I found this restrictor when I was removing tubing to the actuator in the process of packing it up for shipment.

 

Ah, that's a bit different. I thought you were referring to the S4 turbo, so ignore what I said before. S5's have electronic boost control, so they have a factory-fitted restrictor pill in the line between the compressor housing and the tee in the metal line. Since this is going on an S4, you won't need the tee or the restrictor.

What are your power goals? That'll dictate how much fuel you need.

 

I would like to see 300 to 350RWH. I`ve been gathering and preparing to do these upgrades. Injectors have been something I have been concerned about especially.
Based on what I`ve read the ones I plan to use should do the job. I have the Megasquirt which will install with a harness adapter. I also thought about sending a second ECU to RTek so I`ll have a choice. I`m very much open to all input concerning my upgrade plans. I don`t want to screw up my car and I`m not interested in upgrading to the point of making the car less reliable. I realize ANY upgrades can and will affect reliability but I would rather drive my car than work on it all the time So I`m looking for middle ground if that makes sense. I don`t mind spending the money to do this right, I know there are not any "cheap"upgrades.