Bad boost controller?

[Vince]

The TurboXS boost controller I have is set to 25psi. At around 19-20psi
I can hear my HKS wastegate opening and it levels off and holds true to 25.
My question is does the WG opening so soon affect performance?

Also, at 19-20psi, the wastgate is as loud as when its at 25.

Bad controller????

 

[Enigma_Man]

If the turboXS is a mechanical MBC (I'm not sure if it is) you can see if it's functioning correctly by doing an intake leak test, and pressuring your intake. If it starts leaking before it should, then it's malfunctioning in some way.

I've had mine stick _closed_ and not regulate boost at all, when junk built up inside of the housing. I took the adjustment bolt out, along with the spring and ball, and cleaned it all in some rubbing alcohol. There was just some black engine guk all up in it. Yours might be stuck open slightly, and leaking.

Or, that's just how the MBC could work slightly.

It will affect performance a little, because if the wastegate is open, the turbo isn't spooling as fast as possible, which is the goal.

Make sure it's connected up correctly (Is it new, or have you had it on there a while, and the symptoms are new?), and give it a good cleaning if it's been on there a while.

-Jesse

 

[nine5raptor]

Originally posted by Vince
The TurboXS boost controller I have is set to 25psi. At around 19-20psi
I can hear my HKS wastegate opening and it levels off and holds true to 25.
My question is does the WG opening so soon affect performance?

Also, at 19-20psi, the wastgate is as loud as when its at 25.

Bad controller????

You will always have this. Force on a spring is .5Kx^2. The force on the ball from the pressure is (projected area)(psi). When these two are balanced is when you are at a steady boost level. What I am getting at is you have to move the ball a bit as well to allow boost to get to the wastegate and during this movement time, some pressure is exerted on the wastegate diaphragm.

This slack in flow vs. pressure is what causes the WG to open a little early. You could tune it out with an adjustable wastegate arm or a heavier diaphragm. If you go too far though, you will have issues with spike as the boost will have to go higher to open the ball/spring and get the flow needed to maintain the set pressure on the wastegate.