I'd love to see some real data on this...but none exists on this forum.

Jason/Enthuza claims they saw a negligible drop in output on a V8 with the cats he uses...but too many confounding variables exist.

from what I've read, and what I did with the turbo vw, resonators only stop the popping noises and "rasp." It basically made the car sound boring and OEM. I have no resonator and think my car sounds pretty coo / mature / respectable.

bigger mufflers seem to be the right answer for making it quiet.

 

That seems like under 94 dB, ill just have to test it at the next autox after i put my car back together haha.

 

When you put the turbo in, the system you already have it will quiet down a bunch. A turbo exhaust without a turbo is VERY loud. That's what you are currently running. No wonder you were loud car of the day. Add the turbo it will mellow things out considerably.

On Enthuza's site and at Goodwin I remember this being discussed. A turbo exhaust without a turbo is loud. Not a good loud, an annoying raspy loud.

 

while we're whoring out exhaust vids:





stainless header, Enthuza stainless N/A racer exhaust w/ resonated midpipe, resonated testpipe and Borla muffler. Resonators are ANSA/Silverline glasspacks.

 

I had a 3" enthuza and a 3" silverline reasonator and at idle it sounded not much louder than stock. My chevy truck is louder with a turbo muffler.

And when driving it was perfect. No worries of cops, you can hear the radio, spool was awsome!, and everyone around you could tell you where not average. It was not bumble bee, it was quality bass and perfect.