The exhaust is surprisingly quiet, especially since it's a straight through style muffler and some of the pipe bends have been smoothed out. It's loud enough to sound good/not be totally boring, but quiet enough that you're not "that guy" who makes all this obnoxious noise every you make boost in traffic. I also notice the recirc valves working more now since I can hear them over the exhaust better. I can't really imagine a 2.5" rear section that could flow significantly better. Even the perforated pipe section in the muffler is angled to straighten out the flow. Look in the picture below how the inlet is on the side, but the outlet is in the middle. So the internal pipe is angled. The muffler can is straight so it looks better, but it flows more like an angle muffler (i.e. hyper exhaust). It has a nice burble at start up and idle. Of course I'm used to pretty loud cars. My previous exhaust was totally rusted out and was very loud. I also have an LT1 power Camaro with minimal exhaust that is even louder than my Z used to be, so maybe my quiet is different than others.
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90 300zx TT 13.285@106.08 (old stock turbo set up) 94 Camaro Z28 13.751@101.83 03 WRX 13.973@94.88 02 Mazda MPV; four kids and a wife don't fit in the Z. 90 240sx (sold) 16.9@87
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