Fellow diesel lovers....I am looking at getting new intercooler pipes for my 2006 F250 6.0, partly for looks, but with a little hope for moderate improvement for performance. I am looking at intake elbows and in/out IC pipes. I have read a number of threads on 3" vs 3.5" but cannot get any real clear cut answers. I read a post saying performance actually decreased when 3.5" IC pipes were installed as the airflow had slowed too much for any gains.

Question: Is there any flow/performance increase when using 3.5" IC pipes instead of 3" IC pipes with a 3.5" CMF intake elbow?

If using 3" pipes, I would use a 3.5" - 3" silicone reducing coupler, and probably opt for the polished aluminum Mishimoto pipes. (Ford 6.0L Powerstroke Intercooler Pipe and Boot Kit, 2003-2007, by Mishimoto)

If using the 3.5", I was looking at the Carbon Fiber CMF complete intake elbow and in-pipe.
(Ford 6.0L Powerstroke CFM+ Intake Elbow Carbon Fiber 20-113-3xx)

Any feedback would be greatly appreciated, as I am new to diesels.