Looks like a pretty exhaustive study to me.
Sorry, I couldn't help myself.
But other that the one magazine article, I see nothing that counters my assertion that back pressure is never desired. And I don't put much authority in magazine writers.
Quote:
Originally Posted by aerohead
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*So a 410 cid V-8 produces a 26-mph breeze out it's tailpipes at 60-mph.
I can see why the SAE isn't that excited about back pressure.
*We've had electronic noise cancellation technology for a couple of decades.
*In theory,we could create an open pipe exhaust which was totally silent.
*Is there a good reason why we haven't?
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A German OEM parts supplier has been making functional prototypes for about 5 years years:
https://www.eberspaecher.com/en/prod...echnology.html
They market it to either silence exhaust or generate an exhaust note for electric/hybrids, but I don't know of any applications where it is actually used yet.