Headers without cats?
Thread Starter
Melting Slicks
Joined: Sep 2004
Posts: 3,287
Likes: 1
From: Union City CA
Headers without cats?
I think this is what I would like to do and just would like input from the forum on whether it is a good or bad idea.
I have a Vortech supercharger and I am planning on adding LG headers without hi-flow cats. I have heard a lot of people from the forum that had problem with forced induction and cats.
I am planning on purchasing the high flow cats but not installing them until I need a smog check (hoping they can pass on the visual if I pass sniff test).
Just wondering if there is a down side to running the headers without the hi-flow cats? Thanks
I have a Vortech supercharger and I am planning on adding LG headers without hi-flow cats. I have heard a lot of people from the forum that had problem with forced induction and cats.
I am planning on purchasing the high flow cats but not installing them until I need a smog check (hoping they can pass on the visual if I pass sniff test).
Just wondering if there is a down side to running the headers without the hi-flow cats? Thanks
Race Director
Joined: Oct 2005
Posts: 14,555
Likes: 1,255
From: Saint Albans, WV
Race Director
Joined: Oct 2005
Posts: 14,555
Likes: 1,255
From: Saint Albans, WV
Race Director
Joined: Oct 2004
Posts: 10,516
Likes: 2
From: Virginia Bch VA
Cruise-In VI Veteran
Cruise-In VII Veteran
St. Jude Donor '06
CARTEK 2X H/C pkg. Kooks, no cats, Borla way back.
Love the sound and love the unspent gas smell MORE.
The slight drone with the Borlas @1500-1700 is twice as loud. I just plan around it.
Love the sound and love the unspent gas smell MORE.
The slight drone with the Borlas @1500-1700 is twice as loud. I just plan around it.
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Safety Car
Joined: May 2000
Posts: 4,811
Likes: 344
From: Albuquerque NM
My 2000 C5, with heads and cam, no cats did have a smell to it. My 2007 Z06, stock heads and cam, no cats, has no smell to it. High overlap (aftermarket) cams will pass more gasoline down the exhaust and have a smell.
Drifting
Joined: Oct 2002
Posts: 1,898
Likes: 35
From: Fairview Hts. IL
I was worried about the same thing when I removed the cats. Try without. . . 
Instructor
Joined: Oct 2003
Posts: 204
Likes: 0
From: Tacoma WA
Meet State EPA Test?
I think this is what I would like to do and just would like input from the forum on whether it is a good or bad idea.
I have a Vortech supercharger and I am planning on adding LG headers without hi-flow cats. I have heard a lot of people from the forum that had problem with forced induction and cats.
I am planning on purchasing the high flow cats but not installing them until I need a smog check (hoping they can pass on the visual if I pass sniff test).
Just wondering if there is a down side to running the headers without the hi-flow cats? Thanks
I have a Vortech supercharger and I am planning on adding LG headers without hi-flow cats. I have heard a lot of people from the forum that had problem with forced induction and cats.
I am planning on purchasing the high flow cats but not installing them until I need a smog check (hoping they can pass on the visual if I pass sniff test).
Just wondering if there is a down side to running the headers without the hi-flow cats? Thanks
It seems obvious that long tube headers w/o cats will not meet state smog emission requirements. What about with the LG hi-flow cats?
Thread Starter
Melting Slicks
Joined: Sep 2004
Posts: 3,287
Likes: 1
From: Union City CA
I am going to purchase the LG hi-flow cats but just did not want to put them on. Some people with forced induction were having problem with the cats and I was going to put it on if I need to smog the car. I was just asking what people thought about running the car without cats and I think most people say that the smell will get to me.
Melting Slicks
Joined: Feb 2002
Posts: 2,935
Likes: 0
From: Anderson, SC
St. Jude Donor '06-'07-'08
I have been running LGs without cats for about a year and a half and my only complaint is the smell. I am seriously considering putting the hi flow cats on. It is only a problem when I back the car into the garage or a closed in space. It's not a problem when you're running down the road.
Last edited by Maalox; Aug 26, 2007 at 09:35 PM.
Pro
Joined: Oct 2003
Posts: 639
Likes: 0
From: springfield missouri
ok, I tend to cause a stink with my thoughts....but, Simply take the factory cats and chop them in half on one of the two factory welds. throw all the stuff from the insides away. Cut a piece of pipe that you aquired from the local muffler shop that is the same diameter to fit perfectly with the angle of the top of the inside of the cats. Shove them together and reweld just like factory. Now have your tuner disable those O2s. Depending on the state you are in, you will pass o test. Now you will get a headache from noise from your stingers and will go back to cats or install touring exhaust. I'll let you know about the difference in power on FI app. since the first one was a few months ago and the new one with factory cats is tuesday on the dyno. The baseline was 352rwhp stock at 92% outside. Should be a strong car!