Caveat: I'm sure I'm not the first to ever try this. Full credit for this idea goes to Shane@DB Performance; he is always a bad influence
Theory: more boost = more power
Stock turbos taper. Aftermarket turbos taper. How do you try and cut down taper? A BCS seems to do the trick! However, they can be a tish inconsistent, and boost onset is not always as smooth or as early as a MBC. I tried the stock solenoids and they didn't work. So instead, I got a Pierburg 3-port BCS from CBRD (thanks chad! adapter fits PERFECT), ditched my stock solenoids, and mounted this on their little mount.
Here's JUST a MBC vs a MBC+Stock solenoid hybrid on my BBX. I tried both before the MBC and after it with pretty similar results. Maybe 1psi extra boost up top.
Now the 3-port. It is inline with the MBC, between the MBC outlet and the WGA, with the 3rd port 'venting' back to the intake. I'm only using 50% WGDC at 8000rpm so yea, there is some room to grow with this setup I think!
Note the kinda reverse taper, almost self-induced boost creep if you will. It will hold 28 flat or 26 flat or do this 26/27 going up to 28.5 thing pretty easily. This is like the perfect setup: the ease of adjustment of a MBC with the boost holding power of a BCS up top. Tunability is fantastic. I will have to report back on how consistent it is.
I just unplugged my secondary(passive) BCS and set all the tables to zero. No CEL yet.