OK, So I removed just the stock resonators on my 09 XF Supercharged to add a tiny bit more growl like I have done on my E63 AMG.

Here is some pix of before and after below. And before I buy K&N filters I wnated to see what gains could be made first. So I removed my stock filters and cleaned the air ducts from dirt/dust/etc. I closed them back up and made a few runs with no filters to see if there was any difference.Well, I seen no change in sound or power at all! I will not be buying any intake filters unless I buy a ECU tune first.The dual MAFS I hear are very sensitive in these just like my AMG is.
So now I want to find a new or used rear exhaust to add to my Xipipe. I dont know where to find the best,can anyone point me to some good deals so I can make a X-Mas purchase for myself?

The sound after the Xpipe install goes like this:
Start up and idel is still same as it was stock as is part throttle and normal driving.There is no DRONE at all!. Now 50% throttle and a engine load there is some crackle/tinny/buzz at 2500-3000 RPM's only. Full throttle doesnt have this sound.This sound is also present when reving in neutral at that rpm as well.A good rear exhaust section should clean it up alot.The overall sound is still super quiet so I want the rear mufflers to add about 10-15% more PURRR/Growl like my AMG has.Please point me in some directions and discuss what you see below.

 

Removing the air filters does not equate to using K&N filters. After air pases through K&N or other filters air is conducted in a Laminar Flow that speeds air into the intake. I swear by K&N and use them on all my rides. You will improve performance and won't have to change the filter so often. Maybe 1 to 3 HP. in most cases. What do you know about chips for the Jag ECU?

 

I agree with you on a N/A car but a forced unduction car this wont matter.The least amount of restriction on a force fed motor is best for gains.Both my turbo supras use no air filter element at all or an intake tube and make more power this way as well.

Now flashin the Jag ECU will help alot as the tuner can dial in the air intake when we add a cold air intake or use more free flowing filter elements to keep the banks from showing lean and trhowing a code.After the intake and exhaust have been open up more to get air in and out more the ECU tune will show better gains across the board. Add a pulley and even more will be had just from those simple 3 bolt ons. I sure wish somebody knew of a pulley that incresed boost on these more than the standard 2.5 psi bump pulleys that everyone seems to offer? A 4lbs pulley would be perfect.I think somebody else said none of the terminator mustang or gt500 pulleys will fit/work?

 

Even N/A engines suck in a huge amount of air. Figure that air isn't exactly clean, and you're talking about loads of abrasive materials flowing through everything in the induction path. I would never run without filters on a street driven car. Racing engines are torn down regularly and refreshed, so you see them w/o filters. Not so much street cars driven daily and expected to last >100k miles without a tear down. Of course, do what you want because it's your car.

As to supercharged vs.N/A, I would still think that straightening out the air flow is important to power. Perhaps less so as a percentage, but having air flow into the cylinders smoothly rather than turbulently I would think makes for a more even mixture and more power. Anyway, with me it's academic since I would always run filters.

 

im not saying to run without, i was comparing gains only.I sill feel on these Jags a tune is needed with any air path changes to take full advantage of the product.