I bought my 07.5 with the dpf delete, and it was quiet. I deleted the muffler shortly after I bought it, without a noticeable change. I just got rid if the downpipe cat for a 5" downpipe due to the longarm kit I am installing this week.
I took it for a drive with just the downpipe and it is nasty LOUD! I am probably going to have to invest in a muffler for it. The truck goes in for the Longarm kit Wednesday and I am going to run just the downpipe til then, hopefully I won't get a ticket before then!
I probably will get the exhaust extended to the back of the cab for the time being, hopefully that will lessen the noise(at least in the cab)

i did turbo back right off the bat so mine was alot louder :rocking:

Here is the outlet end of the DPF if you were wonderin.. Nice and clean for sure.

But you can't fool the system by bypassing it. I don't know how much noise you guys want really.. I found dropping the DPF/Cat was enough for a little increase in sound, not as loud as my 97 with a MBRP system. I am not a fan of straight pipes really, just too much noise for daily driving and towing.

Mine is straight piped with 5" and it is loud, in summer I usually put the muffler back on because the cops have their windows open LOL:tu:

what did your 85 over cp3 cost powerwagon