Under boosting on new turbo

[xbrandino]

I have recently installed a BNR S2 on my car but I'm having issues with boost control. Originally when installing and taking it for the first drive, I was seeing boost levels of 22-23psi+ (!!!), while wastegate pressure is only 1 BAR. Turns out one of the covers on the back of the turbo was partially blocking the wastegate arm to open and caused it to over boost.

That issue has now been fixed, but when trying to tune the car, not matter the wastegate DC, between 0% to 100%, the boost only stays at wastegate pressure. I don't have any boost leaks or any issues with the vehicle. Is there a reason why this is happening?

I have read that I may have to adjust the preload on the actuator arm so I'll give that a try, but I wanted to confirm with anyone on here if that seems correct.

The vehicle besides the BNR S2 has a full 3" de-catted exhaust, full intake + upgraded MAF for the additional flow and all the supporting mods needed to go more.

Any help would be appreciated.

[mituc]

Post a log. Use this logging preset: https://www.dropbox.com/scl/fi/afnzjbrr ... x17tp&dl=0

[xbrandino]

I'll get logs with that next time I'm out, unfortunately can't go for a drive at this current time. However I do have 2 logs, one which was driving with 100% wastegate and the other which was only running spring pressure at 0% wastegate.

For some reason the forums doesn't upload anything I attach so I'll just upload it to a google drive link.

https://drive.google.com/file/d/1-sA0lp ... sp=sharing

[mituc]

Well, it's hard to tell if there's a problem with these 2nd gear logs. When you can try to take a log in 3rd to put a bit more load on the engine and make the throttle open fully because right now it only goes to like 74% (and there's a significant even though not big difference between 74 and 76-77).
With an S2 the response should definitely be better and you will probably end up shortening the wastegate arm like 2-3 turns, but let's see a 3rd gear log first.

[xbrandinoalt]

Don't mind the account change, can't get into my other one for some reason.

Here is a 3rd gear pull for you, one with 0% wastegate and the other using 80% wastegate with minimal to no change.

https://drive.google.com/file/d/1ctbRS1 ... sp=sharing

[mituc]

Yes, the one with 80% wgdc sounds about right for this turbo considering the amount of air it was moving in the process. However, even in that run you can see the WGDC decreasing with RPM, so whic means you have some boost creep. In the run with 0% WGDC and about the same air flow numbers and boost it's boost creep no doubt.
So you can start by dialling the wastegate arm, lengthen it at least 3 turns and see where you land after that.

[xbrandinoalt]

Alright I'll give that a try, I disconnected the wastegate actuator pipe to force it closed (re-enact 100% wastegate DC) and boost went to 20psi at 60ish% throttle so I know the turbo's capable.

[xbrandinoalt]

Just an update, I've tried re-routing all the boost connections to the actuator and nothing changes, always running 1 BAR no matter the situation. I unplug the actuator and boosts 20psi+.

Currently waiting for my 3-port BCS to come, hopefully that fixes everything.

[mituc]

What is your EBCS setup? What EBCS are you using and how are the lines routed?

[xbrandinoalt]

I'm still using the stock 2-port BCS on the car. I have it so a line runs from the turbo actuator to the boost source on the compressor housing of the turbo. In the middle of that line, there is a T-piece which routes to the 2-port BCS.