X pipe.
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Joined: Jun 2001
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
Lose secondary CATs
Allows for more sound to exit pipes.
Easy to do, just lots of bolts to take R/R.
Elmer
Allows for more sound to exit pipes.
Easy to do, just lots of bolts to take R/R.
Elmer
Always Shiftin'
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From: Central Florida
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I recently installed the EOS double helix x-pipe (link below). It eliminates the secondary set of cats. Low cost, but excellent quality. And installation was pretty easy.
EOS X-Pipe
It isn't really any louder, just a "throatier" tone. Maybe a little louder right at cold start-up, but idle is not much different, at least to my old-man hearing.
To me it was only worth it because the cost was low and I enjoy "tinkering" with my Corvette. Knowing what I know now, I would never spend the money for the higher priced versions. Not enough benefit for the buck!
EOS X-Pipe
It isn't really any louder, just a "throatier" tone. Maybe a little louder right at cold start-up, but idle is not much different, at least to my old-man hearing.
To me it was only worth it because the cost was low and I enjoy "tinkering" with my Corvette. Knowing what I know now, I would never spend the money for the higher priced versions. Not enough benefit for the buck!
Last edited by MacA1979; Nov 4, 2023 at 10:33 AM.
Burning Brakes
Joined: Mar 2022
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From: Hershey, PA
2025 C7 of the Year Finalist - Modified
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The bigger exhaust companies used to sell X-pipes that eliminated the secondary cats. They are no longer allowed to sell them due to EPA rules/regs. EOS as mentioned above seems to be one of the few still selling them without the cats.
Thread Starter
Le Mans Master
Joined: Jun 2019
Posts: 5,481
Likes: 2,190
From: Loveland
This ebay add says it's mounted behind the CAT's. What CAT's are they talking about? The main CAT's or the secondary ones connected to the X pipe. One of the pictures shows very small CAT's on the X pipe, other pictures don't have it.
https://www.ebay.com/itm/32453625982...Bk9SR77u-evyYg
Looking at the BORA install directions, they cut the secondary CAT's off and mount them to the X pipe. Not what I am looking for..
https://www.ebay.com/itm/32453625982...Bk9SR77u-evyYg
Looking at the BORA install directions, they cut the secondary CAT's off and mount them to the X pipe. Not what I am looking for..
Last edited by kodpkd; Nov 3, 2023 at 08:23 PM.
Thread Starter
Le Mans Master
Joined: Jun 2019
Posts: 5,481
Likes: 2,190
From: Loveland
What doesn't make any sense with the new X pipes. You still have the secondary CAT's with restrictions at the front of the new pipe and the same size pipe at the rear of the X pipe exiting the back of the car, so what has been accomplished? Nothing!
Plus,,,,, they have you destroy your original X pipe by cutting off the old secondary CAT's. I want the old X pipe if I want to go back to original.
Plus,,,,, they have you destroy your original X pipe by cutting off the old secondary CAT's. I want the old X pipe if I want to go back to original.
Burning Brakes
Joined: Mar 2022
Posts: 1,101
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From: Hershey, PA
2025 C7 of the Year Finalist - Modified
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It does look like they are keeping the secondary cats on the Ebay link you attached. And you're right, there's no point in buying a new x-pipe if it only installs behind the cats.
Your best bet is to keep checking the forum's here for someone selling a used one that deletes the secondary cats. They do pop up from time to time.
Your best bet is to keep checking the forum's here for someone selling a used one that deletes the secondary cats. They do pop up from time to time.
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Always Shiftin'
Joined: Jun 2000
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From: Central Florida
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This ebay add says it's mounted behind the CAT's. What CAT's are they talking about? The main CAT's or the secondary ones connected to the X pipe. One of the pictures shows very small CAT's on the X pipe, other pictures don't have it.
https://www.ebay.com/itm/32453625982...Bk9SR77u-evyYg
Looking at the BORA install directions, they cut the secondary CAT's off and mount them to the X pipe. Not what I am looking for..
https://www.ebay.com/itm/32453625982...Bk9SR77u-evyYg
Looking at the BORA install directions, they cut the secondary CAT's off and mount them to the X pipe. Not what I am looking for..
Thread Starter
Le Mans Master
Joined: Jun 2019
Posts: 5,481
Likes: 2,190
From: Loveland
This ebay add is the same EOS X-pipe I purchased direct from Extreme Online Store (EOS), located at the link I provided in my post above. This pipe is a double helix x-pipe that bolts right up to the existing exhaust where you remove the stock x-pipe. The stock x-pipe has the secondary cats attached and will be eliminated when you install this EOS x-pipe.
Thread Starter
Le Mans Master
Joined: Jun 2019
Posts: 5,481
Likes: 2,190
From: Loveland
I still can't figure out how the EOS X-pipe connects. They say just bolt on. So what is it? Cut the old secondary cats and install them with the X-pipe or just bolt it on?
EDIT:
I finely found the picture I was looking for. Clearly the X-pipe is long enough to eliminate the sec CAT's. Ordered from Ebay $269 with free shipping.
EDIT:
I finely found the picture I was looking for. Clearly the X-pipe is long enough to eliminate the sec CAT's. Ordered from Ebay $269 with free shipping.
Last edited by kodpkd; Nov 5, 2023 at 11:29 AM.
Safety Car
Joined: Jul 2019
Posts: 3,841
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From: nashville TN
I still can't figure out how the EOS X-pipe connects. They say just bolt on. So what is it? Cut the old secondary cats and install them with the X-pipe or just bolt it on?
EDIT:
I finely found the picture I was looking for. Clearly the X-pipe is long enough to eliminate the sec CAT's. Ordered from Ebay $269 with free shipping.
EDIT:
I finely found the picture I was looking for. Clearly the X-pipe is long enough to eliminate the sec CAT's. Ordered from Ebay $269 with free shipping.
Racer
Joined: Nov 2013
Posts: 402
Likes: 271
I still can't figure out how the EOS X-pipe connects. They say just bolt on. So what is it? Cut the old secondary cats and install them with the X-pipe or just bolt it on?
EDIT:
I finely found the picture I was looking for. Clearly the X-pipe is long enough to eliminate the sec CAT's. Ordered from Ebay $269 with free shipping.
EDIT:
I finely found the picture I was looking for. Clearly the X-pipe is long enough to eliminate the sec CAT's. Ordered from Ebay $269 with free shipping.
Drifting
Joined: Jun 2013
Posts: 1,428
Likes: 478
From: Maryland, USA
eos is direct bolt on, many have bought that one with no issue.
they made it to kind of present the idea it can keep cats with much work.
speed engineering has one as well.
https://speed-engineering.com/produc...t1-lt4-engines
thats all 1 piece, which is even more a plus.
there is no bad or ugly for a catless xpipe because 2 less things to go bad on especially if you track the car.
you get a tad more performance and sound.
they made it to kind of present the idea it can keep cats with much work.
speed engineering has one as well.
https://speed-engineering.com/produc...t1-lt4-engines
thats all 1 piece, which is even more a plus.
there is no bad or ugly for a catless xpipe because 2 less things to go bad on especially if you track the car.
you get a tad more performance and sound.
Thread Starter
Le Mans Master
Joined: Jun 2019
Posts: 5,481
Likes: 2,190
From: Loveland
I ordered the EOS from Ebay, the picture shows it comes with the donut gaskets and it's free shipping. It should be here this week.
This pipe comes in two pieces, I figured I would measure the original pipe and bolt the two together the same length.
EDIT:
Good suggestion MacA1979,,,, I think I will try with the Front bracket facing up to make it easier to bolt the clamps.
I also have the Quickjack and love it. It stays on the floor and I can park the vet over it.
This pipe comes in two pieces, I figured I would measure the original pipe and bolt the two together the same length.
EDIT:
Good suggestion MacA1979,,,, I think I will try with the Front bracket facing up to make it easier to bolt the clamps.
I also have the Quickjack and love it. It stays on the floor and I can park the vet over it.
Last edited by kodpkd; Nov 6, 2023 at 09:46 AM.
Always Shiftin'
Joined: Jun 2000
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From: Central Florida
2025 C7 of the Year Finalist - Modified
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If you decide to move forward with the EOS X-pipe, I would recommend reviewing the thread I have linked below...
https://www.corvetteforum.com/forums...ispreloading=1
The two piece assembly creates some additional installation challenges, but isn't a real issue. MA Z06 had a nice write-up on the thread and I included some information that might also be helpful. Read all the way to the end.
Don't hesitate to PM me if you have any questions. I will be happy to help!
https://www.corvetteforum.com/forums...ispreloading=1
The two piece assembly creates some additional installation challenges, but isn't a real issue. MA Z06 had a nice write-up on the thread and I included some information that might also be helpful. Read all the way to the end.
Don't hesitate to PM me if you have any questions. I will be happy to help!
Thread Starter
Le Mans Master
Joined: Jun 2019
Posts: 5,481
Likes: 2,190
From: Loveland
Good suggestion MacA1979,,,, I think I will try with the Front bracket facing up to make it easier to bolt the clamps.
I also have the Quickjack and love it. It stays on the floor and I can park the vet over it.
I also have the Quickjack and love it. It stays on the floor and I can park the vet over it.
Racer
Joined: Jul 2003
Posts: 460
Likes: 18
From: Conroe, TX
After some research I determined that a 1-piece design was easier to install and overall a better solution, so I went with the 1-piece Speed Engineering double helix X-pipe a few months back for only $249.00+shipping: Speed Engineering C7 Double Helix X-Pipe
Excellent quality, perfect fitment, highly recommended!
Excellent quality, perfect fitment, highly recommended!