It violates federal emission law. Moving the CATS away from the exhaust manifolds increases emissions at startup. You cannot do anything to an exhaust system that changes the as-built emissions certification.

With long tube headers and high flow CATS you will pass emissions once the engine is up to temperature. You will fail visual inspection if someone looks.

 

as in just behind the header? If so, LTs with High Flow Cats, Just behind the headers or 'in the same place'

Yes I have a C5, with TPIS LTs, Random Tech High Flow cats, ( just behind the header) Random Tech X-pipe and open exhaust ie no mufflers.
I have a small cam (224/224 .581/.581 112) and pass OBDII and visual inspection every year


and come on guys, non of you have EVER used 'creative' interpretations?

 

Neither CARB nor federal rules allow for relocation of the cats, nor for their removal or replacement except with exact replacement parts and only then to replace defective parts. All states must comply with one or the other. There is no grey area. The Z06 pieces are not legal on a base car. I aint preaching, I have LTs myself but this is the truth. That no one would notice is probably true. Legal? Nope. It involves replacement with a different part. Here is a cut and paste from the epa website.


Emissions Laws & Regulations – Frequently Asked Questions


What is the difference between the Environmental Protection Agency (EPA) and the California Air Resources Board (CARB)?

The EPA is a federal governmental agency that works to develop and enforce regulations that implement environmental laws enacted by Congress. CARB is a California governmental agency that promotes and protects public health, welfare and ecological resources through the reduction of air pollutants.

What agency establishes the laws that affect the emissions controls on my vehicle?

The State of California has long been recognized as one of the major air pollution problem areas in the United States. CARB was established in part to study this problem and implement changes to reduce air pollution. CARB has been leading the nation in implementation of strict emissions requirements for motor vehicles through the use of emission control devices and bi-annual motor vehicle smog-check program. Vehicles that are labeled as "California Emissions Equipped Vehicles" vehicles meet the emissions requirement of CARB for that particular model year.

The EPA establishes the pollution laws and regulations for states other than California. Vehicles that are labeled as "Federal" emission equipped vehicles meet the emissions requirement of the EPA for that particular model year.

Have other states adopted the California emissions laws?

In recent years, other states have suffered similar air pollution problems similar to those that faced California. Instead of these states enacting their own set of emissions laws, the federal government offered the California laws as an alternative. Instead of having 50 different sets of emissions laws, states must choose between either the California or Federal regulations.

At the present time there are several states that have enacted the California laws (i.e. Mass., Maine, New York, and Vermont) and new vehicles are sold as "California Emissions Equipped Vehicles". You can easily determine the emissions status of your car by referring to the emissions decal that is placed under the hood of your car.

Is my vehicle required to be submitted to a tailpipe emissions "smog-check?

This depends on the state that you reside in and the local requirements. For example in California, smog-checks are required in populated areas, but not in selected rural areas. With laws and regulations changing at an increasing rate, it is very difficult for the aftermarket to keep ahead of these changes. We suggest you contact your local or state agencies for information regarding your emissions laws.

Can I legally replace an emissions sensitive part on my car with an aftermarket product?

In the state of California, it is not legal to replace an emissions sensitive device without the replacement part having an exemption from CARB. Although replacing a particular device might have no apparent effect on the emissions, and the car might even pass a tail pipe "smog-check", the replacement part is still not considered emissions legal. In many cases, the mandatory visual inspection of the vehicle prior to an official state required smog-check may result in immediate failure of the test if a non-exempt part is identified.

A part that has been issued a CARB exemption has been subjected to strict laboratory testing as required by CARB in order to demonstrate that the replacement part will not increase emissions. (These tests are NOT the same as the "smog check" test and often require "cold start" testing procedures in order to test the efficiency of the emissions system during the initial seconds of the start-up cycle.) A part that has successfully passed these tests will be appointed an Executive Order number and will be listed on the CARB website for reference. Every Executive Order part or modification has an assigned number that can be verified by Smog Check stations, BAR Referee stations, or by the ARB. This number should be displayed on or near the emissions sensitive part for reference by a smog check technician.

For a database listing of current exempt parts, visit:
http://www.arb.ca.gov/msprog/aftermk...es/amquery.php


What does it mean when an aftermarket product is advertised as "CARB Exempt" or "50 State Legal"?

Although a part may be advertised as "50 State Legal", this may be more of a marketing statement than reality. Unless an emissions sensitive part has been issued an Executive Order number by CARB, or an EPA exemption, the part is NOT legal for street use. Parts that are typically appointed CARB exemptions include: headers, air filter/intakes, turbo kits, and supercharger kits. Parts that are typically not eligible for a CARB exemption include, but are not limited to: OBD II replacement catalytic converters (as of early 2005, only a few 1997 and later OBD II catalytic converters have been granted an exemption), downpipes or headers that remove or relocate a catalytic converter, and performance carburetor kits. Contact the manufacturer of a product that you are considering purchasing for details regarding that specific component.

An exhaust system that is installed AFTER the catalytic converter is considered a "cat-back" system and is considered emissions legal. (Sound level restrictions may be an issue in your state, check with the exhaust manufacturer or you local authorities for more information.)

Can I replace the OEM catalytic converter on my car with a "high flow" catalytic converter?

The catalytic converter plays a major role in the emissions reduction of a motor vehicle. The vehicle manufacturer has matched a specific catalytic converter to the vehicle to minimize emissions output. Both CARB and the EPA do not allow the replacement of a catalytic converter with non-exempt "high flow" performance replacement unit. In fact, it is technically not legal to even replace a converter unless it has been proven by technician to have failed, and then it can only be replaced with an exempt OEM equivalent unit. (However, enforcement of this requirement is almost non-existent and is the primary loop-hole that allows the usage of so-called "high flow" catalytic converters. Many of these units are sold with the disclaimer as being a "race" component and are not intended for street use.) Due to the hundreds of vehicle models produced over the years, it is virtually impossible to determine by glancing under a car whether the converter is the original unit, a legal OEM replacement, or a non-legal aftermarket "high flow" performance unit. Unless CARB or the EPA decide to take more aggressive enforcement action, the installation and usage of these non-exempt "high flow" catalytic converters will likely continue.

 

If it's defective it will be replaced with an OEM part. If the manufactured part has been discontinued then an approved replacement can be used.

 

Benefit of one-piece Header / X-Pipe?????


What is the perceived benefit of a One-Piece Header / X-Pipe design, as with the new LG Street Headers...compared to a traditional Header into aftermarket X-Pipe and exhaust (ex. Billy Boat, Borla).

I would think that the traditional "seperate" Header, X-Pipe and Exhaust would yield alot more flexability in changing the configurations around if you did not like the performance or sound

 

Within a year many of die hard legal eagles will say, Why are all these C5s stronger and faster, much faster??

Well then it is "Screw it, I WHAT HP." Off come the OEM headers and cats, On go the LTs, High flow cats and straight pipes. Great CAM, then great tune. Even if you never hit the strip or road course. I do recommend going to a road course for a High Performance Drivers Event. You will want the HP and TQ.

And you will find a way.

There are enough great tuners and performance parts retailers around, you wont go to a Chevy dealer again to have any work done.

Each to their own.

 

Bumpster

 

Where I live in OH (part of the year) if you buy a new car, you dont get tested until the 4th year Birthday of your car. So you get a free 4 year pass of doing whatever to your car. I just put in my Kooks headers this weekend for a 3 year heyday on my '07

 

Lucky! Here in the good ole commonwealth of Virginny, we get inspected on the second anniversary and every two years there after. Mine comes up this year

 

Say, Happy New Year! Did you say you got a Z06 exhaust end to end-what's with the LS3 build? Not only interior but engine/exhaust as well? No No wonder you got the new racy booties

 

I always seem to belong to the other 20%..........

 

Me too - that's why I am skipping headers on the new motor and going with a Z06 Exhaust. It leaves some hp on the table - but I shouldn't have to worry about emissions inspections.....

 

Even more lucky is if you live here in the State of Sweet home Alabama-we have no inspection ever. Neither does our adjoining state of Florida. The Chevy dealer will install the headers for ya.

 

Really? Lol