Cat or not?
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
I am guessing you have been hiding under a rock for the last 4 days... 
Check out this thread: http://forums.corvetteforum.com/show...76&forum_id=48
Now, with that posted... The L98 exhaust is highly restrictive.
A lot also depends on where you live. If you are in a state with only a sniff test, then it's easy, just remove the precats and add a highflow main cat.
You see, the precats don't do much except clog up the exhaust system. Once main cat is hot, all work is done by it.
The optimal L98 exhaust is a set of Long Tube headers, High flow bullet cats, x-pipe and pipes out to mufflers.
That setup is worth 50+ hp. It will really open it up, and, it will pass all sniff tests!!!
I would also remove the air pump. That's worth more power. If you go with the 2 high flow cats, you won't need the air pump.
All of this depends on the nature of your emissions testing. If you have visuals, then your hosed. But if you have nothing or sniff only, this will work great.
I would not want to drive one of these cars with headers and no cats, hell, no cats at all would be very loud and boomy. The x-pipe will help reduce resonance, as would a good choice in mufflers.
Check out this thread: http://forums.corvetteforum.com/show...76&forum_id=48
Now, with that posted... The L98 exhaust is highly restrictive.
A lot also depends on where you live. If you are in a state with only a sniff test, then it's easy, just remove the precats and add a highflow main cat.
You see, the precats don't do much except clog up the exhaust system. Once main cat is hot, all work is done by it.
The optimal L98 exhaust is a set of Long Tube headers, High flow bullet cats, x-pipe and pipes out to mufflers.
That setup is worth 50+ hp. It will really open it up, and, it will pass all sniff tests!!!
I would also remove the air pump. That's worth more power. If you go with the 2 high flow cats, you won't need the air pump.
All of this depends on the nature of your emissions testing. If you have visuals, then your hosed. But if you have nothing or sniff only, this will work great.
I would not want to drive one of these cars with headers and no cats, hell, no cats at all would be very loud and boomy. The x-pipe will help reduce resonance, as would a good choice in mufflers.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by goldeneye_vet
Bogus....get that soapbox out of mothballs and get ready! I need another good laugh!!!!!! 
I don't under stand why you are laughing... it's not a laughing matter.
Take a moment and read the posts from TJWong. If you want no emissions controls, enjoy living in China, India and Russia. And don't forget to wear your mask...
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Burning Brakes
Joined: Jun 2002
Posts: 1,001
Likes: 1
From: sd
Originally Posted by bogus
It was never put away.
I don't under stand why you are laughing... it's not a laughing matter.
Take a moment and read the posts from TJWong. If you want no emissions controls, enjoy living in China, India and Russia. And don't forget to wear your mask...
I don't under stand why you are laughing... it's not a laughing matter.
Take a moment and read the posts from TJWong. If you want no emissions controls, enjoy living in China, India and Russia. And don't forget to wear your mask...
I want to drink a beer with you someday and really get you going on this subject as I bet it would get quite interesting. Take it easy bogus......I'm not trying to rattle your cage but when I saw this thread I knew that you would be here chiming away so I had to get a little ribbing in on you. Have a good one!!!!!!!!! To the original poster, sorry if I hijacked your thread!
Burning Brakes
Joined: Apr 2004
Posts: 810
Likes: 1
From: Las Vegas NV
Originally Posted by bogus
It was never put away.
I don't under stand why you are laughing... it's not a laughing matter.
Take a moment and read the posts from TJWong. If you want no emissions controls, enjoy living in China, India and Russia. And don't forget to wear your mask...
I don't under stand why you are laughing... it's not a laughing matter.
Take a moment and read the posts from TJWong. If you want no emissions controls, enjoy living in China, India and Russia. And don't forget to wear your mask...
Clean horsepower is the way to go.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
There will be a sound increase and it will only hurt the environment; just drive behind a school bus or city bus and you will be fine.
Your entire exhaust system is restrictive; your best deal is to install FL headers and true duals. You can even add dual bullet cats to run clean if not legal.
Your entire exhaust system is restrictive; your best deal is to install FL headers and true duals. You can even add dual bullet cats to run clean if not legal.