Is there any advantage to a 4 inch cat back with dpf delete? I have a life wire to address the codes. Just curious if it would be worth doing

 

Clean motor oil. Increased power. a 10% or so MPG gain. Great accelleration. No turbo lag. Cooler EGTs. That's all I can think of right now.

 

As long as you have a tuner, you should delete the cat (DOC) & the DPF.

 

The cat-back wont do much of anything for ya but the dpf delete is another story.

 

Ok I mis ask the original question. What I was asking originally about was the exhaust kit that goes from the PDF delete kit to the tail pipe. Any thing to expect from it? Sound or is it all looks? While I'm asking what could I expect from deleting the cat since I already have lost the dpf?

 

Yeah I wasnt sure of the original question so I followed what the others mentioned.
I just recently put on dual "dpf" back (im deleted already) 4" mbrp. The sound changed noticeably and thats about it. Looks and sound.

 

It's like any other pipe, making the down stream pipe bigger does not increase volume. The squeeze in your case would be the stock down pipe and the DOC/CAT. Most folks remove the CAT because it's a lot easier to do the CAT and DPF as one unit. I've not heard anyone say they thught they gained a lot of breathing room removing the CAT.