Running to much boost. How can I lower it????

[mulot30th]

He will need to lower the wastegate preload BEFORE installing the boost controller since the boost controller will not help him LOWER the preset boost level

 

[FLYBYU]

He will need to lower the wastegate preload BEFORE installing the boost controller since the boost controller will not help him LOWER the preset boost level

Thats what were having him do now. So you legthen rod all the way out? Maybe it's stuck. The hose from the output of the turbo to wastegate actuator is leak free and has nothing in between it? Maybe it's the wrong actuator? I'm not sure whats the right part # for that but i'm sure someone here has it. Are you sure your at the end of rod thread on the wastegate?

 

[machz69]

I know this sounds too simple, but did you disconnect the activation arm and move the waste gate by hand. Could it be stuck?

is it easy to open the gate?.. I tried moving mine by hand and no way, you would really need to pull hard?..but it does open at 6lbs on an air guage but i will have to confirm with my boost guage. Mine is not hitting the tank. I moved it back.
Try doing like i said, put an air gauge on it with air. set your compressor to 7lbs and see if it will open. This might help to find out if it's the gate or the actuator.

 

[mbarryracing]

If you remove the actuator rod from the wastegate arm, the arm / wastegate should flop back and forth easily with NO resistance. If not, it is rusted and sticking and taking more pressure to actuate.

 

[pdrmike]

I had the arm off and it all moves freely, that is how I determined it was all the way open. I opened it all the way and adjusted the arm to keep it open, still 14psi with wastegate fully open. Boy, this is getting fun!

 

[mbarryracing]

You have too much backpressure then! The wastegate can't dump it enough and it keeps driving the turbine.

 

[machz69]

You have too much backpressure then! The wastegate can't dump it enough and it keeps driving the turbine.

Hey that's interesting. Never thought of that?.. that could be why I get a difference in lbs to open the gate with air pressure then when the motor does. So what would be the answer?.. a different spring in the actuator or exhaust?

 

[mbarryracing]

As a total rectal extraction, I'd dare to say that the problem might lie post turbo and in the outlet / muffler? How much restriction do you have in the outlet?
Flow will take the path of least resistance (high to low pressure), if the exhaust pressure is the same on either side of the wastegate port as it is in front of the exhaust scroll, the exhaust will just keep traveling past the turbine... The purpose of the wastegate is to "dump" the exhaust pressure before the exhaust scroll but if it can't the back pressure will continue to drive the turbine.

 

[machz69]

I have the stock exhaust or muffle but i thought all the CPR systems ran on the stock muffler?

 

[mbarryracing]

They might, maybe some baffle broke and lodged sideways or something stupid like that. Just a guess but you could always unbolt the outlet from the turbo and take a peak, etc.
Which way does the outlet face? Away from the gas tank?
I've seen a few rear mounts run without the outlets on a dyno for B/P development reasons... Unbolt it and rip it across the yard to see if the boost is reduced in conjunction with reduced B/P??? I'm grasping at straws here as I am not at all familiar with CPR's...

 

[skidoo]

Droped my exhaust in the tunnel straight off the down pipe lost 2# of boost and sled has never ran better. (apex mnt cpr kit)

 

[FLYBYU]

There is a mod to stock exhaust that cpr reccomends but i just went right to excell exhaust. He wont able to drop the pipe, it will melt the tank.Something is stuck. that turbo is maxed out at that psi. the wastegate is not doing it's job

 

[mbarryracing]

Or it can't do it's job...
Definitely one or the other.

 

[machz69]

There is a mod to stock exhaust that cpr reccomends but i just went right to excell exhaust. He wont able to drop the pipe, it will melt the tank.Something is stuck. that turbo is maxed out at that psi. the wastegate is not doing it's job

What is the mod that he recommends?

 

[skidoo]

gutting the muff