gentlemen,

i am thinking of replacing the large main muffler with an "X" pipe...can someone tell me what size pipe i need? a possible trusted source? ...and any additional thoughts, pro's or con's to doing this ? my '05 XKR is bone stock with 77K miles.
MANY THANKS in advance for sharing your experiences !

xkrface

 

I did a lot of research on this recently. Seems like the large muffler is in fact an X pipe internally. Most that removed it and replaced with x pipe found little difference in sound. I wanted just a little more rumble, without introducing any drone, so I removed the two small turbo mufflers after the large muffler. They are the ones that do the lions share of quieting the exhaust. Pleased with the result so far. If you want really loud, then you will also need to replace the two rear resonators with straight pipe. There are kits available to do both of these replacements, or you can DIY. My Diy took about an hour, and cost me $30. I can always go back in later and do a "better" job. https://www.jaguarforums.com/forum/x...te-xk8-234958/

 

Thank you darbysan !
My train of thought was for a slight performance increase by way of reducing a little back pressure. A little increase is growl would be ok but not too much..just thinking of letting her breath a little easier.
I am thinking the scavenge effect of an x-pipe to help however I have read a comment that it makes our x100’s sound “like a V6”....! ???...
thoughts ?

xkrface

 

PS.... great DIY !
you have thinking of doing the same

 

Someone took off the big muffler and cut it open. Inside, it is wide open- no baffling, with two pipes that have holes in them that work as an X pipe- allowing flow from both sides to mingle. Most that have removed it have found no increase in performance, and little or no sound change.

 

I have a full cat back X pipe exhaust with only rear mufflers and it definitely does not make it sound like a V6. You would probably describe it as more like muscle car, not super loud but a lot more bass to it than stock and a sort of blub blub blub V8 sound you don't really expect from a classy looking car like a Jag.

It made literally zero difference on a dyno, even with all the mods and twin screw blower, so don't go expecting anything more than sound for your trouble.

I will say that you need to be a little careful with exhaust mods, especially with a coupe. You can find resonant frequencies at certain RPM and throttle positions.

If you want a good safe place to start, removing the little over the axle mufflers are good bet and it is the most restrictive piece of the whole system what with the pinched pipe.

 

Max,
I wanted a better sound on my '06 vert also. I discussed possible changes with a local custom muffler shop. The owner felt that the over the axle restriction was not that bad, as the volume was still comparable with the rest of the system. We decided to remove the last 4 (2 per side) mufflers, replace with 2 1/2 S.S. pipes and new oval tips. This gives a nice 'Growl' at idles, and a little more 'roar' at full throttle. Even with the top down, conversation/radio sounds are still well within normal range. We decided that if the noise needed lowering, a pair of mufflers behind the axle could still be added. So far I do not plan to add back any mufflers.
I do not have the space, or inclination for a DIY project of this size any more, so it was all performed at the shop. Total cost was $300.

 

I completely disagree. I first had the Mina exhaust system which removes two rear mufflers. I bought an X-pipe from Chris and it made a massive difference, big change in volume. Car pops and crackles, much more throaty, really amazing sound. The center muffler is an X-pipe but it is more restrictive. Supposedly an H-pipe should give a more muscle car type sound which I'd stay away from.

before:

after:

Probably going to do away with the cats for a higher flowing setup soon, should sound closer to an F-Type.

I've had an amazing number of comments on how good it sounds, even from a GT3RS owner (which is one of the best exhaust notes IMO) and plenty of jealous muscle car owners. Can't really be conveyed in videos.

Jacob

 

Use caution if you lose the Cats. Does Ga. still have vehicle inspections??

 

Yes, I'd go with 200 cell cats likely.

Jacob