2005 F250 all stock 6.0 with 109k.
In AZ. so I gotta consider annual emissions/inspection, but Id like to know what the best cold-air intake and turbo back system and configuration is for reliability and air flow, cat/gutted-cat/cat delete, muffler no muffler, 3.5/4/5/6 ??
I tow a 33 foot fifth wheel occasionally.

 

I would like some pointers for my 2000 7.3 as well.

Like does a Banks or Bully Dog intercooler help mileage in combo with a larger diameter exhaust?

 

Don't bother with a CAI, the OEM one is perfectly fine.

The least restriction is going to be a turbo back exhaust with no cat or muffler. IMO, 4" or 5" is personal preference. I have a 4" system

 

For the 6.0, there is no better CAI than the factory airbox. It'll support 500rwhp with no issues. And it protects the turbo

Get a 3.5" down pipe and cat delete. Dropped my old truck egt's 200f or so