3 Port EBC - Acting Up, Overboosting

Based on the old DYI EBC thread: http://www.mazdaspeedforums.org/forum/f11/poor-man-s-3-port-ebcs-123490/
Installed the self made EBC in 3 port mode (same one CS/GS/COBB/JBR make), soldered up to a plug-in connector, so very PNP and straight forward, just like the GS/CS instructions say.
Problem: Get overboost even with WGDCs at 0% (the overall map is 30% of the old stock EBC map). I logged WGDC of 0 starting @ 2500 rpm, with boost going to from 15psi to 23psi at 270rpm (targeting 17) before fuel cut kicked in. So the LEC/BEC tables did their job, they made WGDC 0 but boost kept rising.
Do I really need to remove the stock turbo fitting restrictor? The instructions for COBB or GS don't say to remove it... There are a few folks who say it's not necessary to remove the pill: http://www.mazdaspeedforums.org/forum/f9/grimmspeed-3-port-boost-control-solenoid-90900/#post1355188
The turbo being on the car, I'd rather cap off the turbo nipple and tee into the BPV vacuum source.

As a side note, does anyone know if these little paths in the bottom part of the EBC do anything?

I was worried about the seal to the top part so I put a very very minimal amount of silicone there to provide a light seal so that that there is no air coming through the plunger opening affecting the ports... but now I wonder if those paths are there for a reason. I really did take great care to make sure silicone did not get squeezed intot he plunger, etc. It really does look like there is a gasket supposed to be there... kind of like the OEM BOV flange gasket.

 

Partial solution - I did have the hoses mixed up somehow. After hooking them up, I am able to maintain boost of 17.5 as targeted, BUT:

Only until 4,300 RPM. This is where WGDC drops to 0 again, while boost stays at 18psi tapering off to 16.5 at redline.

This feels like the restrictor pill is perhaps keeping enough pressure out of the WG diaphragm to avoid opening it when necessary to keep the boost down. I just don't have another explanation right now.

Anyone chime in to confirm?

UPDATE: Switched boost source to tee off the BPV valve, as per CS instructions. Now I am making boost properly, but have trouble getting it over 19psi between 3.5K-5.5K, my WGDC commanded values are into the low 50s now, which I thought wouldn't be the case with a 3-port EBC. Regardless, it's working fine now, the WGDC curve just looks a big different than the OEM one.

 

I had the same problem at first. I had a "tee" with a restrictor in it and would overboost. Swapped the "tee" and it was all good after that

 

Hey guys. Also just hooked up a Mac 3 port and added a 3 bar map sensor to my car. Aside from all that I have a 3” long catless dp, catback, 3 inch intake, vtcs delete cs injector seals and a few other things. 3 port was hooked up in what I thought was interrupt mode and worked fine for the first 50kms than I started experiencing a lottttt of what I think is overboost.

I would start my 4th gear WOT log and the car would hold for a quick second than my RPMS would fly right up and I generally wouldn’t be getting very much acceleration and while doing this it would be hitting near 30lb of boost (targeting 20-23) so it almost felt like the clutch was slipping but I know it’s not my clutch. Any tips for me when I go to take this apart?