Newbie XF owner here, Newbie car guy too. My near showroom condition 36K-mile '05 6Sp NA Coupe is completely stock. I think it's pretty peppy, but I'd like to max out that pep while keeping it aesthetically as stock as possible. I would like to do a tune and throttle body upgrade, as these appear to be the most effective means of squeezing out a few additional horses.

Can someone explain what it is about the stock intake that renders it inferior to an aftermarket CAI?

 

air flow

 

Welcome to the family!
My advice would be to contact Rob at Needswings. He can help you configure your car for what you want it to do.
If you want to increase the power with bolt on upgrades, then you should look here: https://needswings.com/intake-xf You can always put the stock parts back on if you want.

 

1) Air flow is a bit more restricted with the stock setup.
2) Stock setup preheats the air more than the aftermarket "cold air intake". (Cooler air is more dense, so when ignition happens, there is more air mass that will expand and push the piston down with more force.)

For the NA, a "cold(er) air intake", throttle body upgrade and tune are about all you can do for more power. You won't get much, you will spend as much as $3000 for maybe 20hp. I"ve heard claims of 50hp but to my knowledge, no one has shown verifiable test results to supports such statements. Improvements to the SRT setup are another matter, I've personally driven modded SRTs that amazed me.

 

Thanks all, really appreciate the input.

These are springtime projects, so I'll be scrimping and saving all winter and hopefully be back with an update.

And in terms of tunes, between Eurocharged and MSS, any advantages/disadvantages on one over the other?

 

My Crossfire is stock, but if I was to have it tuned, I would go with the MSS.
They are very knowledgeable and helpful.