VCDS and Boost specified

   #1  

senna1

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Hi
When using vcds to view, Boost,, Is the Boost shown absolute, or just gauge pressure,, For example is 2500 m/bar actual boost pressure from the turbo into
the engine, or atmospheric pressure of 1000m/bar at sea level, And 1500 M/bar of boost.
 
   #2  

Uwe

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I don't think I've ever seen anything except absolute pressures. Absolute pressure in the manifold is, after all, what the engine cares about, while relative ("gauge") pressure above ambient is not really relevant to its operation.

-Uwe-
 
   #3  

senna1

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I don't think I've ever seen anything except absolute pressures. Absolute pressure in the manifold is, after all, what the engine cares about, while relative ("gauge") pressure above ambient is not really relevant to its operation.

-Uwe-
I've found my Disc:thumbs: for the the engine i was working on and it is in Absolute.
 
   #4  

BlueR32

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IME, in the engineering and scientific communities virtually everything is absolute to eliminate variables in atmospheric pressure.
 
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Jack@European_Parts

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   #6  

senna1

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Hi Jack.

Good links, not read through the whole site or products, My standalone ecu's run most things including launch/traction control and
turbo engine and N/a. using Alpha-N or speed Density. And some ecu's blending both like M,squirt.The reason i asked about the boost being absolute total,
I have a map from a Bosch ecu EDC15. using winols, of the Boost table, which at 1950,mbar would be approx 1,bar of boost depending on sea level, if the table is absolute, if not then boost of nearly 2,bar seemed a lot for a small Diesel std engine.

As UWE Say Absolute pressure in the manifold is, after all, what the engine cares about, while relative ("gauge") pressure above ambient is not really relevant to its operation.
 
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