Main Cat Question
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
it's part of the AIR system. disconnecting it only slows the cats light off time.
Where do you live? removing the cat is a $10k federal fine... and you will never pass the sniff again.
I am a big fan of removing the entire L98 exhaust and installing a dual system using bullet cats and an xpipe.
Where do you live? removing the cat is a $10k federal fine... and you will never pass the sniff again.
I am a big fan of removing the entire L98 exhaust and installing a dual system using bullet cats and an xpipe.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
It connects to a check valve beside the passenger side exhaust manifold. The smog pump pumps air to the cat through this line. If the line is left open it'll make some noise, although it probably won't be audible if it still terminates under the car.
Team Owner
Joined: Jun 2001
Posts: 26,196
Likes: 0
From: Orlando FL
St. Jude Donor '08-'09
It helps warm up the cat for optimal use.
Mine has all been disconnected when I gutted the cat and removed the AIR system. The line is still attached to the cat housing, but it doesnt do anything. I am too lazy to cut it all the way off heh.
Mine has all been disconnected when I gutted the cat and removed the AIR system. The line is still attached to the cat housing, but it doesnt do anything. I am too lazy to cut it all the way off heh.
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
Team Owner
Joined: Jun 2001
Posts: 26,196
Likes: 0
From: Orlando FL
St. Jude Donor '08-'09
Just make sure you hang on to it all in case you need it. It's "illegal" to remove that garbage...even though its restrictive crap.
I left all my stuff in place, I just rammed it empty. Its 100% there if you look under the car, but its all hollow.
I wanted to get a straight pipe too, but the C4 Vette mechanic I used to take my car too said that I won't be gaining much over the already rammed out cats. It adds a bit more of a raspy sound, but I actually like it.
I left all my stuff in place, I just rammed it empty. Its 100% there if you look under the car, but its all hollow.
I wanted to get a straight pipe too, but the C4 Vette mechanic I used to take my car too said that I won't be gaining much over the already rammed out cats. It adds a bit more of a raspy sound, but I actually like it.
Racer
Joined: Sep 2002
Posts: 407
Likes: 0
From: Alma AR
it's part of the AIR system. disconnecting it only slows the cats light off time.
Where do you live? removing the cat is a $10k federal fine... and you will never pass the sniff again.
I am a big fan of removing the entire L98 exhaust and installing a dual system using bullet cats and an xpipe.
Where do you live? removing the cat is a $10k federal fine... and you will never pass the sniff again.
I am a big fan of removing the entire L98 exhaust and installing a dual system using bullet cats and an xpipe.
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Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
PBnf
Are you wanting to eliminate the main cat with a x-pipe? If so, you will need 2 bullet cats on two fabbed pipes that replace your original front Y-pipe and terminates in the X. Another way is replace your main cat with a hi- flow main cat, then cut off your front Y behind the two precats and extend the pipes forward into the header flanges. Either way it's pretty much custom welding. There are other options.
Are you wanting to eliminate the main cat with a x-pipe? If so, you will need 2 bullet cats on two fabbed pipes that replace your original front Y-pipe and terminates in the X. Another way is replace your main cat with a hi- flow main cat, then cut off your front Y behind the two precats and extend the pipes forward into the header flanges. Either way it's pretty much custom welding. There are other options.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
What do you recommend for the cats, and x-pipe?.
This 900cfm total flow would support a little over 400hp at the crank.
With true duals an Z-pipe would add a little too. To locate the "X", paint stripes down the pipes and run the engine till you see paint burnt or heavily discolored. Install the "X" at the center of the discoloration.
Racer
Joined: Sep 2002
Posts: 407
Likes: 0
From: Alma AR
To locate the "X", paint stripes down the pipes and run the engine till you see paint burnt or heavily discolored. Install the "X" at the center of the discoloration.[/QUOTE]
That's interesting. I've never heard of that method. I'll try it. Right now I have the headers. I'll get 2 cats next. Then finally when my budget allows, the pipes and x-pipe. Just one more thing, the cats come right after the collectors, right?
That's interesting. I've never heard of that method. I'll try it. Right now I have the headers. I'll get 2 cats next. Then finally when my budget allows, the pipes and x-pipe. Just one more thing, the cats come right after the collectors, right?
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
