Opinions on factory exhaust mods
#1
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I pulled off my mufflers today to see how it would sound, surprisingly it was only a tad louder. So than I pulled the middle mufflers and got some sound out of it. Its a little much so I guess the other option is to leave the end mufflers and cut out the middle ones which would be really simple.. The only problem is I cant test it out without cutting and welding... Anyone do just the center mufflers and if so how does it sound? By center mufflers im not talking about the huge one after the cats..
What I'm thinking is since there even smaller than the end mufflers the difference in sound would be even less than no mufflers..kinda pointless IMO but at least it would be free and I wouldn't have to worry about tips and bending metal..
What I'm thinking is since there even smaller than the end mufflers the difference in sound would be even less than no mufflers..kinda pointless IMO but at least it would be free and I wouldn't have to worry about tips and bending metal..
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Last edited by X308XJR; 05-14-2014 at 04:08 PM.
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rogerwilko (07-06-2020)
#2
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A local guy removed the mid mufflers on his 98 XJR, and I got the chance to hear it fairly regularly. Not a whole lot of increase in sound, but at least you could hear it, unlike the silence when all the mufflers are in place and in good shape. I think it's a good idea in any case just to drop some weight. The factory exhaust is ridiculously heavy. If you're okay with some more sound (or actively pursuing it), replacing the mid mufflers with some straight pipe is a great way to get a bit more sound without being obnoxious while dropping about 10-20 lbs in the process.
The biggest difference maker in sound on these seems to be the cats. The same guy later had a custom catless 2.5" x-pipe built, so it eliminated the cats and the first massive muffler that the factory system uses for flow crossover. It was MUCH louder. It didn't sound very good through just the factory rear mufflers IMO. He later finished it all the way out in 2.5" with a pair of Magnaflow mufflers in the rear muffler voids, at which point it sounded GLORIOUS. The AJV8 sounds wonderful with a proper aftermarket exhaust, and he estimated that he dropped close to 80 lbs all told. Can't decide if this is the route I want to go. It will definitely make some better power, and weight reduction is always about the best thing that can happen to any vehicle, but I kind of like the stealth factor of the factory exhaust. It's kind of fun to have a nearly silent car that can move like the XJR can
The biggest difference maker in sound on these seems to be the cats. The same guy later had a custom catless 2.5" x-pipe built, so it eliminated the cats and the first massive muffler that the factory system uses for flow crossover. It was MUCH louder. It didn't sound very good through just the factory rear mufflers IMO. He later finished it all the way out in 2.5" with a pair of Magnaflow mufflers in the rear muffler voids, at which point it sounded GLORIOUS. The AJV8 sounds wonderful with a proper aftermarket exhaust, and he estimated that he dropped close to 80 lbs all told. Can't decide if this is the route I want to go. It will definitely make some better power, and weight reduction is always about the best thing that can happen to any vehicle, but I kind of like the stealth factor of the factory exhaust. It's kind of fun to have a nearly silent car that can move like the XJR can
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#3
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hi, I actually did the same thing
initially I went for straight pipe but it was too loud and losing low end torque but a huge bang once hitting 4k rpm, very uneven acceleration
then I changed to X pipe, sounds good and I "feel" there is some power gain there
initially I went for straight pipe but it was too loud and losing low end torque but a huge bang once hitting 4k rpm, very uneven acceleration
then I changed to X pipe, sounds good and I "feel" there is some power gain there
Last edited by vincent661983; 05-15-2014 at 01:01 PM.
#4
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Im sure eliminating the cat and mid muffler with an x pipe would wake things up but for one thats a good amount of fab work and two, im almost positive that would throw a check engine light.
Virtually free would be eliminating the mid mufflers, end mufflers or both. Or after the center muffler get 2 aftermarket mufflers and put them either where the mid mufflers or rear mufflers go but not both.... Putting them where the end mufflers are limits muffler choice as the pipe position has to be offset/offset same side which from what ive found are flowmaster super 44 or 40 series delta flow (both supposedly loud) or magnaflow 4'' x 9'' oval...
Vincent661983, your saying you straight piped the center muffler, mid mufflers or rears? Im running it now with no rear mufflers and I dont see how it could possibly be considered loud..
Virtually free would be eliminating the mid mufflers, end mufflers or both. Or after the center muffler get 2 aftermarket mufflers and put them either where the mid mufflers or rear mufflers go but not both.... Putting them where the end mufflers are limits muffler choice as the pipe position has to be offset/offset same side which from what ive found are flowmaster super 44 or 40 series delta flow (both supposedly loud) or magnaflow 4'' x 9'' oval...
Vincent661983, your saying you straight piped the center muffler, mid mufflers or rears? Im running it now with no rear mufflers and I dont see how it could possibly be considered loud..
Last edited by X308XJR; 05-15-2014 at 12:57 PM.
#5
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#8
#9
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Info for anyone that can use a sawzall and welder or clamps.
Middle Mufflers are 12.5'' long Tail Mufflers 19'' long
7.5'' wide 8.25'' wide
4.5'' deep 5.25 deep
inlet/outlets middle of muffler offset/offset same side
bypass pipe 13'' long 2'' diameter 19.5'' 2'' diameter but tip side is 2.25''
all 4 mufflers seem to be a strait shot inlet/outlet so no bending is needed.
Middle Mufflers are 12.5'' long Tail Mufflers 19'' long
7.5'' wide 8.25'' wide
4.5'' deep 5.25 deep
inlet/outlets middle of muffler offset/offset same side
bypass pipe 13'' long 2'' diameter 19.5'' 2'' diameter but tip side is 2.25''
all 4 mufflers seem to be a strait shot inlet/outlet so no bending is needed.
#10
#11
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So your running x pipe which replaced the center muffler than which mufflers past that? How does it sound? Xj8 or R
I drove around all today with just rear mufflers removed and I really like it, especially with all the windows down under full throttle it sounds good. I will accept a little more "drone" for some more rumble so I'm looking into aftermarket mufflers to replace the mid mufflers than run strait pipes to factory tips. The only problem is it's a fairly tight fit with the mid mufflers being so small..
I drove around all today with just rear mufflers removed and I really like it, especially with all the windows down under full throttle it sounds good. I will accept a little more "drone" for some more rumble so I'm looking into aftermarket mufflers to replace the mid mufflers than run strait pipes to factory tips. The only problem is it's a fairly tight fit with the mid mufflers being so small..
#12
#13
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The guy I talked to used standoff bungs on the downstream o2 sensors to move them out of the exhaust stream farther which eliminated his CEL from removing the cats, as all it's really looking for is a certain differential of exhaust gas flow from the upstream sensors to the downstream sensors.
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Z07Brandon (02-20-2022)
#14
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Hi I removed the Rear Silencers and removed the Middle 2 Resonators it sounded great until I drove it the drone inside was terrible!
Thinking of putting back the 2 x Mid Resonators and going straight pipe to the rear or do you think I should leave out the 2 mid resonators and just ad the rear silencers back. Happy for it to be quieter and just a bit louder on exceleration... Your thoughts
XJ8 Sport X308 3.2lt
Thinking of putting back the 2 x Mid Resonators and going straight pipe to the rear or do you think I should leave out the 2 mid resonators and just ad the rear silencers back. Happy for it to be quieter and just a bit louder on exceleration... Your thoughts
XJ8 Sport X308 3.2lt
#15
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A local guy removed the mid mufflers on his 98 XJR, and I got the chance to hear it fairly regularly. Not a whole lot of increase in sound, but at least you could hear it, unlike the silence when all the mufflers are in place and in good shape. I think it's a good idea in any case just to drop some weight. The factory exhaust is ridiculously heavy. If you're okay with some more sound (or actively pursuing it), replacing the mid mufflers with some straight pipe is a great way to get a bit more sound without being obnoxious while dropping about 10-20 lbs in the process.
The biggest difference maker in sound on these seems to be the cats. The same guy later had a custom catless 2.5" x-pipe built, so it eliminated the cats and the first massive muffler that the factory system uses for flow crossover. It was MUCH louder. It didn't sound very good through just the factory rear mufflers IMO. He later finished it all the way out in 2.5" with a pair of Magnaflow mufflers in the rear muffler voids, at which point it sounded GLORIOUS. The AJV8 sounds wonderful with a proper aftermarket exhaust, and he estimated that he dropped close to 80 lbs all told. Can't decide if this is the route I want to go. It will definitely make some better power, and weight reduction is always about the best thing that can happen to any vehicle, but I kind of like the stealth factor of the factory exhaust. It's kind of fun to have a nearly silent car that can move like the XJR can![Smile](https://www.jaguarforums.com/forum/images/smilies/smile.gif)
The biggest difference maker in sound on these seems to be the cats. The same guy later had a custom catless 2.5" x-pipe built, so it eliminated the cats and the first massive muffler that the factory system uses for flow crossover. It was MUCH louder. It didn't sound very good through just the factory rear mufflers IMO. He later finished it all the way out in 2.5" with a pair of Magnaflow mufflers in the rear muffler voids, at which point it sounded GLORIOUS. The AJV8 sounds wonderful with a proper aftermarket exhaust, and he estimated that he dropped close to 80 lbs all told. Can't decide if this is the route I want to go. It will definitely make some better power, and weight reduction is always about the best thing that can happen to any vehicle, but I kind of like the stealth factor of the factory exhaust. It's kind of fun to have a nearly silent car that can move like the XJR can
![Smile](https://www.jaguarforums.com/forum/images/smilies/smile.gif)
#16
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Hi I removed the Rear Silencers and removed the Middle 2 Resonators it sounded great until I drove it the drone inside was terrible!
Thinking of putting back the 2 x Mid Resonators and going straight pipe to the rear or do you think I should leave out the 2 mid resonators and just ad the rear silencers back. Happy for it to be quieter and just a bit louder on exceleration... Your thoughts
XJ8 Sport X308 3.2lt
Thinking of putting back the 2 x Mid Resonators and going straight pipe to the rear or do you think I should leave out the 2 mid resonators and just ad the rear silencers back. Happy for it to be quieter and just a bit louder on exceleration... Your thoughts
XJ8 Sport X308 3.2lt
#17
#18
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Previous owner of my car made diy exhaust from stainless steel. All straight through absortion mufflers without h or x. It sounded bad and was wayy too loud to my liking. So I modified it with Dynomax 2.5" welded X to the front and one biggest straight through mufflers I could fit to the back per side. This trsnsfered the sound from tugboat to the european v8 sound. With this setup it was quiet on part throttle and louder on full boost. Except for very narrow rpm range drone.
Then I desided to cut Dynomax open and stuff in muffler wool as much as I can. This made exhaust very quiet to inside. But you definetly can hear from the outside that there is something else in than downsized 4 banger. Of course drone is still there. But it is now just below acceptable level. I'm thinking to install small superturbos as middle mufflers to kill the drone.
Then I desided to cut Dynomax open and stuff in muffler wool as much as I can. This made exhaust very quiet to inside. But you definetly can hear from the outside that there is something else in than downsized 4 banger. Of course drone is still there. But it is now just below acceptable level. I'm thinking to install small superturbos as middle mufflers to kill the drone.
Last edited by Vauxi; 07-11-2020 at 07:17 AM.
#20
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I'm also looking into upgrading the exhaust on my '02 XJR. There is a lot of good information throughout this forum, with some interesting opinions on the setup. For example, earlier threads (some dating back to 2012) favored a 'siamesed' style X-pipe over a "true-X" or "parallel X." The poster advocating the 'siamesed' crossover stated that the true-x was for American cars and didn't work on Jaguars. I'm assuming that would be due to the firing order (?) Then there's the different setups with some people deleting the center muffler replacing it with their choice of X-pipe, while others retain the center muffler and delete the mid-mufflers.
There's also the choice of which grade of steel to use. Not being a metallurgist and pretty much failing every physics course that I was forced to take, I had to read up on the differences between the grades of stainless steel. It turns out that 304 stainless is more resistant to rust than 409 stainless. There's also a variant to 304, the 304L, that is easier to weld. So, comparing a couple of brands of products, Magnaflow uses 409 and Borla uses 304. I've decided to go with the 304, with a few pieces of 304L thrown in.
I've also had a cat rattle going on for a while, so I ordered the Nameless Performance downpipes with 200 cell cats. These are made with 304 stainless and metal substrate instead of ceramic. As a side note, I chatted with another member that got these about seven years ago, and he stated that his fell apart after a couple of years. I had already ordered when we had our discussion, so hopefully Nameless has upgraded the cats since then. Then I noticed that Nameless has been removed as a preferred vendor from the forum list. The downpipes are sitting in my garage waiting for the big project to begin, so I guess that I'll find out how they hold up.
With all of this in mind, my choice is to go with a siamesed crossover, followed by Borla mid-mufflers and retain my Mina rear silencers. I've found some good sources for the 304 pieces that will be needed, with the crossover pipe being the most expensive; the rest can be had for a slight increase in price over the 409 stainless. I've also decided to use 2.25-inch pipes after the cats,which are 2.5-inch.
For the crossover, I'm looking at Stainless Works 225xss 304 crossover pipe. For the mid-mufflers, the Borla 400495s on both sides. Ace Race Parts has about the best prices on 304 and 304L for the pieces to put this all together. Also, the crossover pipe and Borla mufflers have notched pipe ends so that I can use clamps instead of having it all welded together. I like that just in case this setup doesn't work out.
Thoughts before I go on my spending spree?
There's also the choice of which grade of steel to use. Not being a metallurgist and pretty much failing every physics course that I was forced to take, I had to read up on the differences between the grades of stainless steel. It turns out that 304 stainless is more resistant to rust than 409 stainless. There's also a variant to 304, the 304L, that is easier to weld. So, comparing a couple of brands of products, Magnaflow uses 409 and Borla uses 304. I've decided to go with the 304, with a few pieces of 304L thrown in.
I've also had a cat rattle going on for a while, so I ordered the Nameless Performance downpipes with 200 cell cats. These are made with 304 stainless and metal substrate instead of ceramic. As a side note, I chatted with another member that got these about seven years ago, and he stated that his fell apart after a couple of years. I had already ordered when we had our discussion, so hopefully Nameless has upgraded the cats since then. Then I noticed that Nameless has been removed as a preferred vendor from the forum list. The downpipes are sitting in my garage waiting for the big project to begin, so I guess that I'll find out how they hold up.
With all of this in mind, my choice is to go with a siamesed crossover, followed by Borla mid-mufflers and retain my Mina rear silencers. I've found some good sources for the 304 pieces that will be needed, with the crossover pipe being the most expensive; the rest can be had for a slight increase in price over the 409 stainless. I've also decided to use 2.25-inch pipes after the cats,which are 2.5-inch.
For the crossover, I'm looking at Stainless Works 225xss 304 crossover pipe. For the mid-mufflers, the Borla 400495s on both sides. Ace Race Parts has about the best prices on 304 and 304L for the pieces to put this all together. Also, the crossover pipe and Borla mufflers have notched pipe ends so that I can use clamps instead of having it all welded together. I like that just in case this setup doesn't work out.
Thoughts before I go on my spending spree?
Last edited by hispeed42; 08-03-2020 at 04:09 PM.