Manual Boost Controller Disconnect?

[scmguru]

I'm looking to disconnect a manual (dial a boost) type controller and return back to stock.

With the knob turned fully clockwise, the boost has never gone over .8 bar or so, when I turn it counter clockwise, it gets to .8 bar but not as quickly.

Would fully counterclockwise = stock?

From what I can tell, the boost knob is under the dash and has 2 lines running to it.

It looks like one of the lines goes to the top of the wastegate and I'm not sure where the other goes to.

Sorry for the newbie Questions.. I'm just now learning about P cars.

[rsrfan]

Clockwise should increase boost. One line will be your pressure line most likely from a "tee" in the line conecting to the side of the wastegate from the intercooler. The other line runs to the top of the wastegate and puts pressure on the top of the diaphram preventing it from opening thereby increasing boost. To disconnect, you must find the pressure source and cap it, ( remove the "tee" or cap ) otherwise you will have a boost leak. The line to the top of the wastegate can be cut to approximately 8". This will serve as your wastegate vent.

Fully counterclockwise should be stock

Hope this helps,

[scmguru]

Thanks I'll do some digging around and see if I can locate where the lines are going in the engine compartment.

Just to confirm, the line coming off the intercooler should go to the side of the wastegate, yes?

[mark houghton]

Originally Posted by scmguru

Thanks I'll do some digging around and see if I can locate where the lines are going in the engine compartment.

Just to confirm, the line coming off the intercooler should go to the side of the wastegate, yes?

The side of the WG is the pressure side from the intercooler. The top is simply a vent to atmospheric pressure. Boost controllers either work by putting pressure into the vent side (thus preventing the diaphram from moving until that pressure is relieved), or by blocking the boost signal to the diaphram itself through the side port. My boost controller works by blocking the signal to the WG until it reaches a pre-set threshold and a solenoid opens to allow the boost to travel to the WG. Really good boost controllers I think use a combination of connections to the vent as well as the boost feed...which is what you probably have. Mine is homemade and serves the purpose well.

[rsrfan]

Originally Posted by scmguru

Thanks I'll do some digging around and see if I can locate where the lines are going in the engine compartment.

Just to confirm, the line coming off the intercooler should go to the side of the wastegate, yes?

Yes. The "dial a boost" controllers differ from the controller that Mark (me too) is using. The pressure line from the intercooler to the wastegate side port is "usually" tee'd into - to run to the controller under the dash.

If you follow the lines, all should become apparent. Please let us know how it goes.

[scmguru]

Thanks guys.. I've got intercooler seals/o-rings on order, as soon as they get here I'll follow the lines.

The boost controller does have an effect on boost but doesn't seem to be behaving like you would think it should.

With the dial turned all the way counter-clockwise, I get about .7/.8lb boost but it comes on at a higher RPM.

With the dial turned all the way clockwise, I get the same .7/.8 lb of boost but it comes on at a lower RPM.

The peak sustained boost is about the same.. the only difference (other than spool up) is when the dial is all the way up, the boost will spike to 1.0-1.1 when shifting @ high revs.

I checked the wastegate and it definitely has 2 hoses attached to it, (side and top), however, the side hose looks like it may be original. Turbo is stock, as is exhaust and wastegate.

If the boost control was hooked up properly, I'd think that the car would overboost @ all the way counter clockwise..

Very odd..