I posted a while ago about having problems with how my boost controller acted.

After hours of thinking and reading, I decided that this might caused by the way I set up the vacuum lines for my external wastegate.

I have a 38mm Tial XWG.Right now this is how I route the vacuum lines.

----------------------------------------------Tial XWG has 2 vacuum nipples (1 on the top, and 1 on the side).For the top: Hotpipe vacuum nipple -> T -> B/C Solenoid -> Top nipple

For the side: T -> Side nipple

Problems: Whenever I let off the gas after boosting, the BOV vent and the WG opens.Whenever I punched it, It build boost up to 0 psi and then the WG opens for a fraction of a second, and then It closes and build boost all the way up until my set boost.---------------------------------------------------------

Solution (Please comments and give advices/inputs):

I am going to junk the T fitting (well not really, its going to be used at different line).

For the top nipple: Hotpipe nipple -> B/C solenoid -> Top nipple

For the side nipple: Brake Booster -> T -> Side nipple

This way, the side nipple will act independently instead of being interrupted by the B/C solenoid.Plus, this will prevent the WG from opening whenever I let of the gas pedal (Since brake booster vacuum is sourced from the intake manifold after the throttle body plate).

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What do you guys think of my game plan?Inputs please

TIA

Where are you sourcing your EBC's boost measurement? If the wastegate opens a bit when reaching 0PSI it seems something is wrong with the EBC boost signal or settings, cause most EBC won't open the solenoid until 0PSI is reached, then it opens and holds open until desired boost is reached, then closes (WG control of course, actuator control is the contrary).

I myself have it like this:

Hotpipe -> Side nippleColdpipe -> Solenoid -> Top nipple

The boost drop across the IC might prevent me from high boost... but at this point in time it can save my ***. If I have issues I'll change the signal from the coldpipe to the hotpipe.

By the way... if u are gonna use the brake booster signal.. make sure to use it BEFORE the one way valve in the line, if you have it after... you'll never see boost.