2013 S8 K&N Filter
 

Can you use two 2013 A8 4.0T K&N filters for the S8?

Anyone change their air filters yet?

Anyone do any mods to their S8?

Looks like the over 50 crowd is happy with stock power?

Wow! I don't own an S8 and am not (yet) over 50, but even I find your comment needlessly offensive.

How about consider the fact that the D4 S8 is a brand-new model? No one has developed a tune for it yet, no exhausts have been built, etc, etc. I doubt that a drop-in K&N filter will appreciably improve upon stock power levels (which are under-rated by the factory, in any case). RS6/7 power should be easily attainable with a tune - perhaps significantly more. How about you give it a while before writing off an owner group as non-enthusiasts, even though they just ponied up a significant amount over a standard A8 for the "go-fast juice"?

K&N = performance subtract
 

I'll hit the substance of it even harder; just visiting from D3 board.

K&N's are a great way to kill expensive MAF's. Posted on many times on D3 board and earlier on C5 board (w/ my 4.2 there). And even more insidious you don't even see the performance subtract happening as it fouls the MAF.

But what the heck, dealers, Bosch and Hitachi all love 'em; sells more parts and service. Oh yeah, and I'm in my 50's.

Ran K&N's back to my Weber 3/36DGAV on a C1--as in carburetor, the era from whence they really came. Gave up on them once MAF's came to dominate and I saw a few too many coated intakes w/ the telltale red oil--no matter how well you oil them (very lightly) or even brand new. My VAG COM instrumented 4.2 where it demonstrably went down 20% on the (nominally) measured MAF airflow--meaning in turn it leaned the mixture--was the nail in the coffin. And for that matter, on any motor with twin air boxes (including my W12) and especially any blown induction, the intake and filters aren't typically going to be meaningful restrictions anyway on a well designed Audi system to start with.

Couple of more nails (bugs) for the K&N coffin
 

Also forgot to mention that as we know from the D3 board with both the S8's and the W12's with the twin air boxes, either the 40K D3 W12 air filter and tune up interval or the 60K S8 interval leaves the (paper) air filters pretty fouled with insects and plant debris to begin with (let alone dust)--the air intake path is very short and direct from the grill area. Easy to blow the filters out mid life w/ an air hose in < 2minutes, but I would hate to be cleaning and oiling these things at as little as 20K intervals. False savings on the "savings" idea too. To be clear, I live in the well paved coastal suburbs out of the hard winter snow and road sand and with relatively few insects--SF Bay Area.

Here's a D3 W12 air filter from about a month ago w/ 20K miles on it from prior change. That's on a 6.0, with the 6.3 presumably pulling yet more air and the current turbo S8 probably doing similarly under boost: