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Greddy Overboosting - help

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Old Apr 1, 2014 | 10:54 PM
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Greddy Overboosting - help

i am having issues with my greedy ebc overboosting. Im running Alpha 28s.

Here are some details. If i turn the boost controller off, boost rises to .85 bar and holds steady in all gears. This is expected

Now, if i turn it on, and have set, gain and start boost (start set) all on zero, i get the same results as if its turned off - .85 bar. However as i start increasing the set, i start to see an overboost/spike. The higher the set, the higher the spike. Ie - if i have the set at 1.25bar, its pikes to 1.25 then drops back and holds steady just under 1.1 bar.

I have all of the other values at 0. ie no gain and no start boost. I have tried increasing the gain, but i still see a spike (not sure if its worse or not)

Im at a loss for what the issue is. I have the solenoid where the n75 valve is. The only think i can think of is maybe in need to reduce the length of the vacuum lines and move the solenoid closer to the wastegate and pick up the boost of the turbo housing.

HELP?????
 
Old Apr 1, 2014 | 10:59 PM
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this is an example - set is 45%. gain and start are zero
 
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Old Apr 2, 2014 | 08:14 AM
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Originally Posted by LQQK
this is an example - set is 45%. gain and start are zero

Gain or i call it how hard the boost kicks in needs to be set to 50% because if you set it to zero you will get a late spool then it will come all at once which causes your spike.
 
Old Apr 2, 2014 | 11:31 AM
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^ worth a shot. Vacuum lines ID?
 
Old Apr 2, 2014 | 12:04 PM
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leave gain at 10% set gain at .8 bar...
then try to run 1.2 bar.... make sure the limit is lets say 1.3 bar...

I dont like the A28s on the EBC... for some reason Ive seen this on a car too... so hard to set it up... you might have to check the Wgs on the turbos... I say 14 psi to crack open..
 
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Old Apr 2, 2014 | 05:02 PM
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Originally Posted by 996tt550hp
Gain or i call it how hard the boost kicks in needs to be set to 50% because if you set it to zero you will get a late spool then it will come all at once which causes your spike.


My understanding was that gain controlled the boost creep at high RPMS - at that the set gain (now called start boost) controlled the peak. I thought that increasing the setgain caused it to peak/spike more.


but then again, I am not sure about any of it anymore, so ill give this a shot and report back.
 
Old Apr 2, 2014 | 05:06 PM
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Originally Posted by MARKSKI@911tuning
leave gain at 10% set gain at .8 bar...
then try to run 1.2 bar.... make sure the limit is lets say 1.3 bar...

I dont like the A28s on the EBC... for some reason Ive seen this on a car too... so hard to set it up... you might have to check the Wgs on the turbos... I say 14 psi to crack open..


Mark - ill try these settings again - specifically the setgain. I have been having that at zero, thinking that the higher the setgain, the greater the spike/overboost as the setgain is meant to control spool. The new controller has two different spool settings - either "control" or "normal" - maybe the new controller works different and having zero setgain is my issue. Ill give this a shot!!!
 
Old Apr 2, 2014 | 06:11 PM
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Originally Posted by LQQK
Mark - ill try these settings again - specifically the setgain. I have been having that at zero, thinking that the higher the setgain, the greater the spike/overboost as the setgain is meant to control spool. The new controller has two different spool settings - either "control" or "normal" - maybe the new controller works different and having zero setgain is my issue. Ill give this a shot!!!
Do u have a prefec b spec II?
If so leave gain at 10% always.
Set gain is fine at .8 bar if u run 1.2 bar. But if u run 1.4 to 1.5 bar set it to 1.1 bar.
These settings work. The test is probably a mechanical issue.
Make sure your limit is 1.3 bar if u run 1.2 bar - at least .1 bar higher then tw boost u want to run. Otherwise u will be bouncing off the limiter
 
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