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Old 04-07-2015, 12:10 AM   #2043
CSG Mike
 
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Quote:
Originally Posted by Thorpedo View Post
Whether the engine is speeding up and hitting 7400 where the acceleration is cut, or the engine is at 7400 steady and the acceleration is cut makes no difference. There are no further forces speeding the crank speed up, so it simply does not speed up due to any sort of momentum whatsoever.

It HAS to be a data acquisition/intake tract evacuation/electronic delay issue of some sort. There is no argument here, as you said, "it is physics". My vote (guess) would be the further expansion of the compressed gases in the intake combined with the delay of the electronics working out what is happening.
The discussion up to this point, at least on my end, has been simplified down quite a bit, but yes, there is a momentum in the rise of the RPMs, which will cause it to continue to rise, even when the throttle is closed.

It is not a data acquisition issue. I've observed it on other cars.

I really should start a separate thread for this; when the evidence is laid out, it will make sense, as does the math.

I'm not the type to make random, wild claims, without empirical evidence to back up my findings.
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