Quote:
Originally Posted by RobAGD
While this is not a strictly SRT engine question because I have also seen it in the 6.1 and 5.7.
But when datalogging the car using a a DashHawk or a Predator there have been rather consistant harmonic or knock in these cars at 3700-4500 ish rpm.
Is there a natural harmonic ( false knock ) in these motors in that range or is it real knock that seems to be rather presistant?
-Robert
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I think you're trying to eyeball knock and it's not that simple. The knock sensor system used across Chrysler engines is fairly complex and very accurate. The data you're seeing, on top of probably having a great deal of aliasing due to data rates over the diagnostic connector, shows amplitude but that is a very small part of the calculation. The engine is baselined on dyno with some very expensive equipment and deviations to this baseline (mostly a frequency component) are evaluated for the presence of knock. Without a PhD in signal analysis (and significantly better equipment) you're unable to interpret the data you've gathered for knock. Most of the other parameters available on aftermarket dataloggers are pretty straightforward and usually accurate.