ive gotten so many mixed answers so ill post again in one short post

ive got the apexi avc-r and I was wondering if it supposed to allow me to boost lower than the spring that is in the wastgate. (I've been told yes and no here)
If it doesn't, i've got an internal wastegate that is SUPPOSED to be .5 bar but ive seen it shoot higer than .6 and i cant lower it with the boost controller at all. i even set it to .25 bar at 20% duty with no luck.
Do I turn the rod shorter or longer on my internal wastegate to lower the boost? (ive been told both ways here)

I just wanted to get a few things cleared up that have been bugging me. You all have been great help here and I one day hope to be the boost master like many of you that already are.

 

In order to completely answer this question you need to know exactly how and why a wastegate does what it does. A wastegate is just a valve that controls exhaust. The valve is held shut with a spring. This spring is rated to a certain pressure. When boost develops pressure is allowed to enter the wastegate and oppose the pressure of the spring. As the pressure increases towards the springs rated rate the wasegate opens.

the only way to lower the boost is to change the rate of the spring so it doesn't hold the valve shut so tightly.

I'm not 100% positive about how to adjust an internal wastegate by changing the rod so i wont' feed misinformation.

 

ok thats what i figured, now i just need to figure out how to manually adjust it.


[Modified by Aeka GSR, 8:48 AM 4/18/2002]

 

you want to find a way to get a weaker spring (as suggested) or lengthen the arm. since the arm is attached to the valve in the wastegate, lenthening the arm means that you're opening the wastegate up...

of course, you should have a boost controller to see if it really works.

good luck

 

These guys are on the right track.

You want to lengthen the actuator arm to lower the boost. Two things will happen.
1. The valve will start to open at some lower boost level.
2. It will open all the way much faster and close slower.

Since you have a boost controller, the first doesn't matter. If you didn't then boost would build slower. Can you picture that?
As for the opening much faster and close slower, the controller duty cycle may be harder to setup because the wastegate actuator will be affected by the exhaust pressure more since you essentially weakened the closing force on the spring. understand?

Your best bet would be to replace the actuator. Yoiur cheapest bet would be to lengthen the arm.

Randy