Well I can definately report that the reverb from my ATP DP does cause some negative correction that was not otherwise present running the oem DP. There is absolutely nothing touching as I went over the install with new bolts and gaskets tonight.
I was thinking of taking it in to the exhaust shop and utilizing the oem bracket in some way and attach to the ATP. I also noted the rubber hanger nearest the flex pipe on the DP essentially is not doing anything. It is loose with no tension on it, so that will need some adjustment or even just a shorter rubber.
Something else I was thinking about is the oem brass gasket from DP to CBE. I wonder if the 2.5 DP to 2.??? OEM CBE is causing some strange vibration as the openings do not much all that well.
Anyone got any other ideas?.???
I am keeping my fingers crossed, but I think I found my knock/ping issue. I have been +6 over the last few days since my visit to the exhaust shop.
What I found is that the OEM CBE straight piped with OEM DP on OEM hangers worked very well and that was how my tune was done with Randy. Add the ATP DP into the equation with the very raw sound that is makes, combined with the fact that the flex pipe on the ATP is rather stiff compared to the floppy oem style. Well sir, you just created a giant tuning fork. Literally the entire is exhaust was ringing from front to back. It was confirmed it was not touching anywhere and decided the easiest fix was to stiffen up the exhaust hangers with some leftovers from the shop. Bang!!! The exhaust note even sounds awesome now.
The conclusion from the shop was that the oem gear that normally still would be attached or even any aftermarket muffler would quell any vibes being sent through the system. So essentially it was not ATP DP in itself causing the vibes but the shitty oem hangers that some have previously been reporting to cause rattles.
My only problem now is the I don't want to reinstall my Boomba RRM because I forgot how smooth the car was before I installed it. Shes purring like a kitten.