Yea, I searched.

So, if I'm right, the only difference between the two is that the XKRS has no resonators and has an x-pipe (H on the XKR). Is the muffler exactly he same as the XKR though?

Thanks.

 

If the XKR came with the Performance Active Exhaust (PAE) then it has an X pipe not an H. I believe the XKR-S has the same system so the back box would be the same.

 

Sounds correct.

The XKRS doesn't have the two resonators that the XKR has, right?

 

is that pic of the stock XKRS exhaust?

 

The xkr and xkr-s also share a different back box

 

XKR-S centre pipe



XKR-S rear muffler



The differences to the centre pipe are obvious.

The XKR-S rear muffler has larger diameter pipes coming out of it, larger valves, larger tips which are polished. Internally they are different as well, it's open inside with one of the pipes removed, the other pipes being larger than the standard XKR one.

The 5.0 XK, XKR and XKR-S centre pipes and rear mufflers are all interchangeable, same diameters, same fitment. You can put an XKR-S rear muffler on an XK, the XKR-S centre pipe bolts up to the standard XKR rear muffler, etc

 

thank you very much for the detailed info.

too bad the muffler is different. my buddies xkrs sounds amazing, and so much better than my 5.0 xkr.

I will be doing the res delete and adding an x-pipe, but I think that a lot of the sound difference will still be in the muffler, unfortunately.

 

Performance gains are mostly from the centre pipe in my opinion. I had a similar design made for my 4.2 XKR and with the stock rear muffler (and corrected tune) the gains were considerable.

 

I've not physically checked it myself, but a friend of mine put a borescope down the pipes of an XKR-S muffler, and he tells me that the U-pipe sections are not there.

The pipes marked in red.



Not sure exactly why it would be done that way, but that's what he tells me.

 

That is a picture of my 2012 XKR with the PAE option. It does not come with the twin in line mufflers but only the rear back box with the vacuum operated outside pipes. I assume this is the same as the XKR-S .

 

My question would be is there a different part number for the back box on an XKR vs XKR-S.

Just did a quick search and found that there is a different part number for a 2012 XKR and XKR-S back box. C2P24867 for XKR and C2P24865 for the XKR-S. Also the price is different with $1700 for the R and $3800 for the R-S

 

Yes the PAE option is the same exhaust as the XKR-S, same centre pipe, same rear muffler.

Yes as you found, different part numbers, different prices for the rear mufflers.

 

Yep, now we know for sure that the muffler on the PAE and XKRS is different than on my non-PAE 2010 XKR.

With that said, this is my plan....to add an x-pipe and delete both of the small center resonators/mufflers, and keep the stock rear muffler. I think that should give me a much improved sound, but not add in any drone, as the stock rear-muffler will be in place. Thoughts?

 

Now you know, but I knew this for a long time already...

Keeping the stock XKR rear muffler and keep the active exhaust operating (don't pull the fuse) it's absolutely dead quiet while cruising, no drone, until you put your foot into it and then it screams.

For example with my XKR, I have 400 cell cats, straight through centre pipes with x-pipe (more or less the same as the XKR-S) and the stock XKR rear muffler, with the active exhaust still functional. It's a total Jekyl & Hyde between cruising and wide open throttle.

 

that is exactly what i'm looking for!

am I right in thinking that the first "can" after the cats is a resonator, and the second one is more of a muffler?

 

That I couldn't tell you, I haven't seen inside the two cans on the centre pipe.

Some people have put the XK centre pipe on an XKR, and reported an improvement in the sound, there's a thread here in the forum "XK exhaust on XKR is win" or something like that. The XK centre pipe only has the rear can on it.

My friend dropped off the XKR-S pipe last night, here you can see it with my stock 4.2L XKR centre pipe.



I don't have a regular 5.0L centre pipe here to compare it with.

 

The 5.0 XKR center pipe with the PAE looks the same but it may be a larger dia. pipe.

Also I believe the standard pipe with the 2 resonators are just straight through perforated pipe. I would assume the pipe is wrapped inside with glass but I don't know for sure.

 

interesting and tnx for that pic.

my 5.0 2nd can (closest to the rear axle) looks much different than both on the 4.2. my first can by the cats looks exactly like the 4.2 first can.

 

so would those be doing more muffling of overall DB, or toning down something else like resonance?

 

I would assume their function is to do both. Has anyone deleted them and run straight pipes (no X ) to the back box and if so what results did they have with noise and resonance/drone.