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Boost issues brainstorm

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Stanwood, WA, USA
#1
So I’m looking for a little brainstorm from the community. I have a X47r setup with all accompanying mods. My problem is for the first couple pulls after the car first gets to operating temperature I can hit and hold 27.5psi but after that it falls to 24.5-25psi.I have replaced the wastegate actuator and all intercooler piping,coupler and clamps and the problem still persists. I know this is a new problem cause it didn’t do this while tuning on 92oct and changed when I went to my e30 tuning but the problems is there no matter what has I am on. There is also a slight whistle I hear when I just start to come out of vacuum into boost that I didn’t notice before. I have had the car boost leak tested and could find any problems there.
 


TyphoonFiST

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Rich-fizzield
#2
So I’m looking for a little brainstorm from the community. I have a X47r setup with all accompanying mods. My problem is for the first couple pulls after the car first gets to operating temperature I can hit and hold 27.5psi but after that it falls to 24.5-25psi.I have replaced the wastegate actuator and all intercooler piping,coupler and clamps and the problem still persists. I know this is a new problem cause it didn’t do this while tuning on 92oct and changed when I went to my e30 tuning but the problems is there no matter what has I am on. There is also a slight whistle I hear when I just start to come out of vacuum into boost that I didn’t notice before. I have had the car boost leak tested and could find any problems there.
Hybrids are known for whistling* it's very common. Does it hold 25lbs constantly after WOT? Or does it flutter?

Sent from my SM-N975U1 using Tapatalk
 


OP
D
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Thread Starter #9
Have you done a Kam reset lately? It most likely has gotten used to your driving style and may need to be relearned

Sent from my SM-N975U1 using Tapatalk
Ok I found out what that is but how would that affect the boost on the first 2-3 pulls go from 27psi to 24psi?
 


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#10
Could it be your boost loss is caused by temperature. Such as the temp sensor for the Charge Air Temp. If I were designing one of these engines I would be certain to limit boost as charge temps rise because not doing so would create huge issues with engine knock. Yeah I know, there are timing controls. However if charge temps rise along with increased pressure due to supercharging Auto Ignition can happen. Back in the 1960's some cars had fuel shuttoffs to shut the fuel off when you turned off the ignition because they could "diesel".

While I am pretty sure that you increased the size of your intercooler it seems to me that you may need an even larger intercooler. Because it appears that as your turbo is heated up from consecutive runs it becomes hot enough to cause an increase in your Charge Temperature.
 


OP
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Thread Starter #11
I don’t think so cause the intercooler I have is capable of handling the heat of a bigger turbo then the one that’s currently on the car. Also with it being this time of year in the pnw my charge temps never go over 60 degrees
 


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