I'm trying to find the best pressure source for my Tial external wastegate. Form reading around some people like to come off the manifold to get the actual boost seen by the motor. Some say just to come from the compressor cover on the turbo. Tial's diagram shows the source before the throttle body, some people say after the throttle body is ok?



This is what I had planned to do along with a Greddy B Spec II.


1. From the manifold to the lower nipple of the wastegate.

2. Nipple on compressor cover to NC on boost controller solenoid.

3. Solenoid COM port to the top wastegate nipple.



Does it sound like a decent plan or should I change it up a little? What has worked for you?

 

I would think it would open quicker if you hook the bottom nipple of the wastegate to the compressor housing, possibly preventing boost spikes. That's what I'm planning to do as of now, especially since I plan to run on wastegate pressure for a while until I'm confident of the basic tune.

Hopefully someone with firsthand experience can chime in.

 

You want to come off the compressor...

 

Ok how about this.



Of the compressor to a T. One side of the T going to the side nipple on the wastegate, the other side of the T going to the NC port of my boost solenoid then out the COM port to the top of the wastegate.

 

Do what GReddy's instructions say.

 

IIRC, Greddy wants you to get vacuum from the FPR for the boost pressure sensor input thing (on the back of the unit). I've got the stock turbo, and there was only one way for me to hook up the solenoid. There should be a pressure source coming from the turbine to the wastegate, and it's a rather large vacuum hose. I think it was NC and COM just like you described.

 

I think this may help.

http://www.greddy.com/img/PHP/products/pdf/689.pdf

and this

http://www.tialmedia.com/documents/w..._wginstall.pdf

 

That's for the electronic measurement of manifold pressure, not the pressure source for the wastegate.

 

I have mine coming off the compressor housing to the boost control solenoid, then from there to the wastegate.