To my understanding,
the worst thing you can do to a Diesel is restrict the airflow to the intake.
(Same fuel, less air = high EGT?)
Intake, and exhaust is always the #1 thing to do to ANY car to begin adjusting the performance envelope away from what the factory provided.
Sorry, but you will have to provide empirical data to make me believe that a factory airbox with a paper filter is better than a 3" pipe going into a 2.5" hose directly to the turbo. (and look again, the stock element is NOT EVEN CLOSE to my admittedly oversized air filter in dimensions.)
Basically, you are trying to make a case for the stock intake...?
Nothing personal, but I want more from my car than the factory intended.
Factory design has many factors: Overall comfort for 99% of car buyers, and cheap cost trump outright performance.
Now all I have to do is undo those things!
Guess what, I am also getting ready to install a 3" Downpipe into a 2.5" SS exhaust system...
That is far bigger than factory too....
You guys must not like going fast.
Thanks anyway!
-Brad