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Discussion Starter · #1 ·
Here's a question I've been meaning to ask for quite a while, but was afraid to ask. I see boost posts say "peak at Xpsi then hold at Ypsi". Is this with the assumed ending "under accelleration "? My boost peaks at 16psi when my foot goes down, holds at 11psi while the RPM go up, then dumps to 0 or slighly vac on level ground at constant speed. I've never driven a different R, so I have no comparison except what I read here.

Thanks for keeping the flames low.
 

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It peaks under wide open throttle which is seen more with a tuned car...but it'll go back to the set psi.....when driving at constant speed it is possible to have 0 boost/vacuum. Which is normal
 

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Discussion Starter · #3 ·
Awesome data set, I'll put it in excel and look at it in a graph.

Interpreting the comments, a good thought model correlates boost pressure to the throttle, which makes sense: more fuel needs more air.

Still, it makes me think I've got something to check. On the way home I tried a few things. I hit WOT in 4th and spiked 20! Then dropped to 16 for a short moment, then stepped down again to about 10 when I let up the throttle but it leaked quickly away and dropped to -10 at steady speed and near 0% throttle. Your description makes it sound as if level cruise should have around 0psi, not a -10vac.
 

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Discussion Starter · #4 ·
Aha! Just realized your data does answer my main question exactly: constant acceleration.
 
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