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Discussion Starter · #1 ·
Figured Id post a topic separate from my build. Installed a boost gauge, and i am getting only 2.5psi under WOT. Decided to take a look at my CBV and waste gate.

here is a video with some info. https://youtu.be/8_aSuTL7ucI

The wastegate seems to be properly adjusted. When i apply pressure to the CBV and waste gate, it slowly leaks back down. Do you think these readings are normal? I am also thinking of the TCV as an issue if i dont have any boost leaks.

The only repairs ive done on the engine are a new pcv system.
 

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Bosch ME7 is a "power on demand". You'll have zero boost while transmission is in parking or neutral and much less than max while it's in 1st or 2nd gear. And even in the 3-5 gear the boost is not directly related to the pedal position.

Mine peaks at about 11 PSI (Hilton stage 1 + new stock Volvo turbo + 3" downpipe) and pulls constantly at about 10 for prolonged* time. "Prolonged" means "a few seconds", then the car reaches its top speed limit :)

Also not all boost gauges are very precise. I read the boost value from MAP, in the same way like VIDA/DiCE do.
 

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Discussion Starter · #3 ·
I've got a Hilton stage 2 coming with parts to go with it. I'll read the boost with VIDA, but I'm sure my Bosche boost gauge isn't reading off by that much. 2.5psi is too low
 

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Bosch ME7 is a "power on demand". You'll have zero boost while transmission is in parking or neutral and much less than max while it's in 1st or 2nd gear. And even in the 3-5 gear the boost is not directly related to the pedal position.

Mine peaks at about 11 PSI (Hilton stage 1 + new stock Volvo turbo + 3" downpipe) and pulls constantly at about 10 for prolonged* time. "Prolonged" means "a few seconds", then the car reaches its top speed limit :)

Also not all boost gauges are very precise. I read the boost value from MAP, in the same way like VIDA/DiCE do.
This.

Also, don't get too focused on boost numbers. Peak boost will vary quite a bit depending on ambient conditions, elevation, temperature, and pressure because the ECM calculates torque using air mass. Cold high pressure weather systems have a higher air density therefore the engine can meet the torque demand with less boost. At elevation or in hot lows the turbo needs to create more boost to generate the flow required to meet the torque demand. Too hot and the ECM will pull boost/timing to protect the engine.
 
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