Contour Enthusiasts Group Archives Forums Modifications Forced Induction Wastegate vacuum line routing

Okay, I'll liven it up in here.

The instructions ADC sent are of extremely little help, and though I am becoming more familiar with this setup by the minute, one thing strikes me:

The Tial wastegate has two vacuum/boost connections- One at the base, and one on the top of the diaphram. The instructions that came with the Profec-B I've installed are not extremely clear (most written in another language) as to what should be connected to each vacuum input of the wastegate.

The diagrams appear to say that the bottom vacuum line needs to be hooked up to a constant vac/boost source (i.e. vacuum tree). However, there was no connection for the top shown- Is this where you want to feed the input from the boost controller solenoid? Or, do I want to leave the top diaphram connection open and use the bottom connection for the output of the solenoid?

Thanks in advance.

The bottom of the wastegate should go to either the compressor housing or some other source of vac/boost. The top should go to the boost controller since it is an electronic one. If its a manual boost controller it would just got in line with the hose coming of the bottom of the wastegate. If i am not mistaken tho you will need another vac/boost source for the controller also. From there it is just some wiring.

Be careful here. The TiAL wastegate works OPPOSITE to a normal built in waster gate. Supplying pressure to the top nipple INCREASES boost, and conversely on a built in wastegate's actuator, supplying pressure to the nipple DECREASES boost.


For you boost controller you want to connect NOTHING to the top nipple, then on the lower nipple you connect the pressure signal FROM the boost controller to that. The the sighnal TO the boost controller should come from the INTAKE MANIFOLD.

i am just going off what is on me and a friends turbo B-series CRX with a AVC-R controller so others may be different.

Take your pressure line somewhere off the intake between the compressor discharge tube and the throttlebody. Feed that into your boost controller. Then take the boost controller output and feed it into the fitting that is close to the base, or the mounting bolts if you will. This will open the diaphragm when pressure is applied.
IF your boost controller has two line for a Delta gate wastegate then look for a picture diagram first and then hook up both output lines to the two fittings. Chances are it won't. If it doesn't then just hook up the one line and leave the other fitting open. You can't have uncontrolled pressure on the outer fitting.

According to TiAL's Technical Page, it is supposed to be hooked up as the Profec-B showed- Standard, non-futzed-with vac/boost line to the base, and your adjustable boost valve (or manual regulator) to the top...



Going to fire it up, not going to set the Profec to add any boost until I'm out of break-in anyway...

Just to clarify things since I'll also be using a Greddy Profec B EBC and a Tial 38mm WG, from my understanding atleast...

1) The Profec B head unit AND the side port of the wastegate get a vac line off of the intake manifold.

2) The INPUT for the Profec B gets a vac line that comes from the charge pipe between the IC and turbo.

3) The OUTPUT for the Profec B has a vac line that runs to the top/actuator port of the Tial WG.

I've come up with this after checking with TiAl and Greddy.

Dan,

That is for a needle valve style boost controller.
The inner fitting gets a pressure signal and the outer fitting gets the same signal so that there is no movement. When the boost is the right level it just closes the needle valve slowly until the rate of air intering the outer fitting is balance with the rate of leakage out the vent corresponding to the desired boost level.

Swazo NO!

For a Tial wastegate you need to tap into thew BOTTOM port with the signal from the EBC. That way - it'll act like a standard buit-in wastegate.

That's how I have mine manual boost controller hooked up.

Hence the more pressure I allow PAST the MBC the LESS boost I get as it OPENS the wastegate - just like a regular wastegate setup.

The other way connecting it to the top works in reverse. the more pressure that goes to the TiAL the MORE boost you get as it holds the wastegate closed longer.

I was just going off of the installation sheet from Greddy for an external wastegate and the profec b.



What I gather from this post and mixed with what Greddy notes, I should...

1) Run vac line from intake manifold to head unit
2) Run vac line from charge pipe to EBC's input
3) Run line from EBC's output to WG's side port
4) Let top WG port vent to atmosphere