Well, I've searched and read until my eyes are blury, and I think that I know the answer...but I'm going to ask anyway. Are high flow catalytic converters legal in the good old USA (well, at least 49 of the states...already know about California)!? I was about to order a couple until I saw the comment "off road use only". What I believe to be true it that it is against federal law to remove the original cats if they are performing properly. Now, most of what I have seen is that manufacturers of these high flow systems say that they are legal in 49 states...but is that for off roading? I'm concerned about them being street legal, mainly in the Commonwealth of Virginia. Now, I know that the common thought is that we are hot rodding, and that has always been much about being the outlaw, laws be damned. Well, I'm older and wiser now, and I want to get as much out of my 2005 Maggie RT as I can, but I want to be legal about it. I'm not going to be street racing, but I love the thrill of putting the hammer down on occasion, when it's safe, and getting up to highway speeds. I have put on a K&N CAI and Flowmaster Force II Exhaust System, along with a Hurst Competition Shifter, and I love the sound and feel of the Maggie. I was reading about all these other mods, including the shorty headers and high flow cat systems, as well as the Predator, but as I said, I want to stay legal. I know that the cats are important to the environment...didn't care at one time, but as I said...I'm older and wiser now. It's nice to be able to breath the air without choking and coughing! Anyway, any comments would be appreciated. I know that people certainly feel differently about these things and opinions vary...but that is what being an American is all about...right? Wantin' to stay legal in Virginia!![]()
Good Luck on getting a straight answer. this topic has been beaten to death in the past and there are all kinds of wives tales and he said she said. Every state and county are different, the Vehicle manufactuers have a stance on the subject too. But i will subscribe, becasue there is a "TON" of knowledge on this forum that might be able to give you a better understanding, and maybe, just maybe, we might hsh out the truth!![]()
2007 Steel Blue Metallic MSRT8...Magnaflow cat back. 6.1L Hemi Registry #1253
"Support Coast Guard Search and Rescue...Get Lost" Hemi Registry 1253
I would personally read through the vehicle laws and regulations for three areas: Your Town, Your County, and Your State. Those are the ones that're applicable to you. Start with the lowest, and see what they say, and work your way up. If none of them have a law specifically barring them, and allowing no exemptions, then they're illegal, and you'll be running on a prayer. If they don't have a specific law barring them, well, what Federal Agent is going to pull you over, and put a gun to your head for having hi-flow cats?
Warning: The above post probably contains 2 or 3 times as many words as necessary.
2005 SXT AWD. Purchased in March of 2009. Totaled on January 16th, 2013. 75k excellent miles together.
1982 Isuzu I-Mark Diesel. Haphazardly acquired January 2010.
1981 Honda Twinstar. Salvaged from my backyard in 2009.
2006 Volvo S60R. Acquired Feb 1st, 2012.
1966 Ford F100. Acquired March 30th, 2012.
Well I have heard that the SLP Loudmouth 1 cat-back (cat delete) is an offroad system, while it certainly has that "off-road" loud sound it's not illegal because it is a cat-back system, so removing your stock catalytic converters and switching to high flows is NOT illegal ( unless your in California )
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'10 Charger R/T- Road & Track package, SLP Loudmouth 1, K&N CAI, 93 octane CAI Predator tune, Jet 180 t-stat
'10 Challenger SRT8 - MOPAR CAI, MOPAR (Corsa) cat-back exhaust system, all around Infinity Kappa 6.5"-6x9 speakers, and a 10" Kicker Solo Baric subwoofer.
'05 Magnum RT- R.I.P.
the only safe way to do it is to call the department that are in charge of emissions and ask them
trufiber ram air hood, diablo sport tuner w/ 93 oct. gas on the 91 oct. tune, ported and polished lower intake manifold, ported and polished throttle body, magnaflow muffler, blastin bobs 10 db exhaust system with the 4" tips, big bully cia, big bully catch can, 160 degree stat, jet hot coated jba shorty headers, lowered and ridin on nitto 420's 255 45r20
fastest time- 15.532@ 89.52
"Speed never killed anyone. suddenly becoming stationary, now thats what kills you."
Catalytic Converter Laws
http://www.epa.gov/oms/consumer/warr95fs.txt
Rules for Replacing Converters
In 1986, the U.S. Environmental Protection Agency issued new guidelines for the construction, efficiency and installation of aftermarket catalytic converters. All CleanAir converters listed in this catalog have been designed, tested and manufactured to meet this policy.
In addition, CleanAir converter listed in this catalog is appropriate for use under the current requirements of the California Air Resources Board (C.A.R.B.).
E.P.A. guidelines state that replacement converters may be installed only in the following situations:
1. The vehicle is missing a converter
2. A state or local inspection program has determined that the existing converter needs replacement
3. Vehicles manufactured prior to 1996 must have more than 50,000 miles, and a legitimate need for replacement must be established and documented
4. In cases of OBD Il-equipped vehicles (1996 and later), the O.E. manufacturer's 8-year/80,000-mile warranty must have expired and a legitimate need for replacement must be established and documented.
Please note that Federal law prohibits removal or replacement of a properly functioning O.E. converter.
When replacement of the converter is appropriate (as outlined above), the E.P.A. further requires that:
1. It be installed in the same location as the original
2. It be the same type as the original (i.e., two-way, three-way, three-way plus air/three-way plus oxidation)
3. It be the proper model for the vehicle application as determined and specified by the manufacturer
4. It be properly connected to any existing air injection components on the vehicle
5. It be installed with any other required converter for a particular application
6. It be accompanied by a warranty information card to be completed by the installer.
having had my 300c refereed for high flow cats and long tube headers, I found a bit of data on it back then, and yeah, I had no leg to stand on.
Last edited by Mr. iNCREDIBLE; 08-16-2011 at 11:29 PM.
"Scars heal... glory fades, and all we're left with are the memories made, Pain hurts, but only for a minute, Yeah life is short so go on and live it; Cause the chicks dig it" - Chris Cagle
So it basically comes down to if you have emission inspections and if it would pass. Kinda like tinted windows and lights, it may be illegal but people do it anyways.
05 Magnum Mineral Grey RT Hemi Reg# 00310
Your only gonna get in trouble if you get caught.
2005 Magnum RT AWD 344AWHP/358AWTRQ
FRI Sidewinder Cam, Johan Tune, Edelbrock Headers, JBA Hi-Flo Cats, Magnaflow Catback, 180* T-stat, aFe Stg II CAI, 85mm Throttle Body, SLP 25% UDP, Catch Can, Taylor Shortys, Freak351 Trans Box , Eibach Pro Kit Springs & R1's. Interior, Engine & "M" Emblems by Billet Tech, R/T Emblems, Magnum R/T Grille, Black Heads & Tails, Eyelids
Tinted windows become illegal at a certain percentage, all tinted windows are not illegal.


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