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Old 10-03-2022, 12:35 PM   #10 (permalink)
Blacktree
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The Prius Experiment - '07 Toyota Prius Base
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Quote:
Originally Posted by Logic View Post
Quite so Blacktree thx.
But wouldn't the fact that the pressure pulses are smoothed out through the mufflers be a large part of that termination effect?
I'm not sure what you're trying to say. But on a normal exhaust system, the exhaust pulses won't be reflected (i.e. terminated) until they reach a significant change in the exhaust pipe geometry. That might happen at the catalyst or the resonator, or whatever, depending on the design of the exhaust system. But that length of pipe won't be tuned for a power boost at any usable RPM.

The whole point of the termination box is to make a place for the pressure wave to reflect, so that section of pipe can function as a header extension. The pressure wave will reflect at the end of the exhaust pipe (the pipe coming from the engine). And the box itself acoustically decouples the two sections of the exhaust system. So the stuff downstream of the box doesn't affect anything upstream of it.

PS - I know that math is specifically for an 8 cylinder engine, because I asked David about it.
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