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Old 10-26-2005, 03:05 PM
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Quote:
Originally Posted by sperry
IIRC, a Y-pipe will propigate a sound wave out both branches opposite the input, regardless of the shape of the Y. Where as a "2-in" resinator or cat won't as long as the internal volume of the resinator/cat is significantly larger than the pipes leading into it.

When there's a decent sized volume change from the pipe to the resinator, there's a pressure drop. It's this pressure drop that will prevent the sound wave from one pipe traveling back out the other pipe. Essentially, it's the location of the resinator that determines the "tuned length" of the exhaust.

Someone correct me if I'm wrong, I'm new to this topic!
Sperry,
The issue here is the amount of energy reflected back. A "Y" will only reflect back 1/2 of the energy (as Harvey noted) back up each pipe. My question to Harvey was how the internal design of the Cat (i.e. the volume and any internal reflections that might be present within it) would affect the amount of energy reflected back up each pipe.
-Bill
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