I also did the hole saw thing on my buddies powerstroke, and it's not notably loud.
I don't know, mine is pretty much a hole through the middle, and its quieter above 3000 than below.

I like this resonator design, the Moroso spiral flow, it seems it's called.
Edit: doesn't seem to be available in enough sizes, I'd need 2 inch. Looks like a turbo with glasspack is still the best solution.
thats a moroso spiral flow muffler.. its not a resonator, or a glass pack, but a welded muffler.. they are awesome..
we have a pair on our aluminum tube frame sand rail (500+ hp corvette 327 powered) and they are very pleasant at idle.. but once you get on it, you can definitely tell they are an OPEN muffler..
im sure on a TD they sound REALLY good..
Believe it or not,It's not actually loud )probably because of the stock size pipes)
And I've only had it over 3500RPM 2X--when I missed a shift going into 5th entering the highway.(dumped into 3rd) With the gov mod-holy crap ! The exhaust was the last thing on my mind ! Redlined pretty damn quick-but didn't come apart. I had replaced all the shifter bushings and ball,but the adjustment wasn;t quite right.
You bet I adjusted that correctly,after that mishap.
Mike
I have my governor modified, with it fully shimmed. I take the sum*** up past 5k every single time i drive it

LOVE IT. Sounds sooo good, I'll have to post a video.
ok, well, idk whats wrong with your guys's cars, but mine was OBNOXIOUSLY loud.. and im a kid.. i like loud. and it was too loud for me..
Probably had exhaust leaks and/or the exhaust didn't exit from under the vehicle..
I'm sorry but even my v8 straight off the long tubes wasn't too loud for me..
Kev ya just a kittykatt