Problem with boost on the dyno

Bobby

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no i suggest you go to the tial 44mm waste gate i had a problem with the turbonetics one. but my problem was the opposite i had a 8psi spring and then it would creep to 12psi. i switched and it cleared right up. ps i also use the aem boost controller. also i meant earlier that you need to get vacuum from the intake mani to the boost solenoid then to the waste gate. get the bov from the mani too
 

PNR Welding

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no i suggest you go to the tial 44mm waste gate i had a problem with the turbonetics one. but my problem was the opposite i had a 8psi spring and then it would creep to 12psi. i switched and it cleared right up. ps i also use the aem boost controller. also i meant earlier that you need to get vacuum from the intake mani to the boost solenoid then to the waste gate. get the bov from the mani too

I can deal with the opposite problems. I dont think it is the case of the wastegate though. If it was the wastegate then that would mean that the wastegate would be opening from the one side to keep the boost level and then opening at the otherside from the exhaust pressure and letting the boost out. I doubt that spring could do that. Easy fix for it though. Cut the tube to the exhaust and let it vent to the atmosphere.
 

PNR Welding

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try every thing i said first then if it doesnt work try a different waste gate.

Yea definately will. Start with BOV then move on to attack that BOV. I have the BOV coming from the manifold. But the turbo is giving the boost to the solenoid for the boost controller. Is there a specific reason why you changed that to the manifold? I guess it will read a more accurate boost from the manifold, I can easily move it there if need to be, then just cap off the turbo side.
 

GI Joe

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Yea definately will. Start with BOV then move on to attack that BOV. I have the BOV coming from the manifold. But the turbo is giving the boost to the solenoid for the boost controller. Is there a specific reason why you changed that to the manifold? I guess it will read a more accurate boost from the manifold, I can easily move it there if need to be, then just cap off the turbo side.

I have a 44mm with the same problem.
Tial says to hook it up just the way you have it bov to manifold w/g to turbo
A hole in the w/g diaphram would cause this problem
 

Simon

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What about checking the solaniod and making sure everything is working with it? I know they have failed in the past. Usually putting some pressure on one side while there is power to the solanoid will cause it to "click" so you know it's working. AEM may have a diganosis procedure for it.
 

PNR Welding

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What about checking the solaniod and making sure everything is working with it? I know they have failed in the past. Usually putting some pressure on one side while there is power to the solanoid will cause it to "click" so you know it's working. AEM may have a diganosis procedure for it.


We eliminated that by going off of the wastegate spring pressure. We turned off the AEM BC and it still did it off the wastegate.
 

TurboX

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I know you say you have a 9lb spring but dont take that as being the boost you will see. I have a 9lb spring myself and only saw 7.5 with my Eboost off, it could be a combination of things. Does the AEM have a Boost correction or sensitivity setting ? I have Eboost and was seeing a drop up top, I adjusted the sensitivity and corrected the problem.

Good luck
 

Bobby

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the reason i take the vacuum from the mani is it is the actual pressure that the engine will see. if you take it from the turbo there may be a pressure drop from there to the intake mani. that is really the only reason i do that. it is just a little more accurate for the motor.
 

GI Joe

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here is an example of the problem 19 to 16 psi
 
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PNR Welding

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Well we tightened the screw on the BOV and still nothing. I guess we are going to attack the wastegate now. We might put two springs in there intertwined and see if this is the problem. That should keep it closed and not let it stay open to see if this is our problem, then I will order the Tial 44mm.
 

GI Joe

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Well we tightened the screw on the BOV and still nothing. I guess we are going to attack the wastegate now. We might put two springs in there intertwined and see if this is the problem. That should keep it closed and not let it stay open to see if this is our problem, then I will order the Tial 44mm.

I'm putting 60 psi on top of the gate with my controller...still the issue????I dont get it...
 

PNR Welding

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I'm putting 60 psi on top of the gate with my controller...still the issue????I dont get it...


So your saying that you have your controller putting 60psi on top to keep the wastegate closed and you are still seeing boost drop off?
 

TurboX

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Dave, did you turn off the AEM or totally pull it out of the system ? 70% Duty cycle seems high for only 8-9PSI
 

turbotr

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Well it's maybe not the cause here, but I do recall years ago that some turbo Buicks with big turbos (back when a 76 was new and big) were dropping boost like that and it was very puzzling. Turned out that some part of the intake setup was actually collapsing under heavy air draw. Like the cone air filter that many used back then for example. Something to consider at least. guess could easily eliminate that possibility by removing the inlet piping from the compressor inlet.

TurboTR
 
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Bobby

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I'm putting 60 psi on top of the gate with my controller...still the issue????I dont get it...


sounds like a bad diaphragm. if you put that much pressure on the top is should not even try to open until you double the spring pressure. once you double the spring pressure that is all it has to give. then you have to up the spring pressure. so a 9psi spring will only do 18psi or so. mine would only do 16-17 and hold it. so i just up graded to a 14 psi spring so i can make at least 25psi on c16.
 

GI Joe

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sounds like a bad diaphragm. if you put that much pressure on the top is should not even try to open until you double the spring pressure. once you double the spring pressure that is all it has to give. then you have to up the spring pressure. so a 9psi spring will only do 18psi or so. mine would only do 16-17 and hold it. so i just up graded to a 14 psi spring so i can make at least 25psi on c16.

I have heard that before but witht the ams 1000 why should it matter? The 60 psi from the bottle justs holds the gate closed until it needs to open...then it shouldbe strong enough to hold it a 13 19 whatever as long as it needs to...just asking because I dont know for sure but I have heard the thing about only being able to control to twice the spring rate
 

Bobby

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from my under standing that is all you can go on any spring is about twice the spring rate. just buy a stronger spring and see what happens. if worst comes to worst you are only out $15 or so
 

TurboPete

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from my under standing that is all you can go on any spring is about twice the spring rate. just buy a stronger spring and see what happens. if worst comes to worst you are only out $15 or so

Thats what I thought as well but I have a 8.5 psi spring in the wastegate and Im able to turn it up to 24#s no problem .



Pete
 

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