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Old 10-02-2022, 03:55 PM   #5 (permalink)
Blacktree
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The Prius Experiment - '07 Toyota Prius Base
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Quote:
Originally Posted by Logic View Post
David Vizard's Pressure Wave Terminator/Termination Box:

Fools the 'Branch' into thinking it's exhausting into open air by cancelling out all the pulses in the exhaust before they go through the muffler/s.

NB
That the rule for the PWTB is that it must have a volume of at least 8X one cylinder.
Preferably 11 to 15X the volume of one cylinder.
I'd like to offer a couple clarifications.

1) The pressure wave box doesn't cancel out the exhaust pulses. It terminates them. When the pressure pulse reaches the end of the pipe, it reverses and goes back up the pipe. The box allows you to have the benefits of tuned length header extensions, while also having a "real" exhaust system.

2) That volume calculation is specifically for an 8 cylinder engine. Hence the "8 times cylinder volume". The calculation also assumes a single pipe exhaust. Another way to look at it: the box needs to be at least the total volume of the cylinders feeding into it, preferably 1.5-2x.
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