I have a question:

I've been looking at High Flow Cats in order to gain power but to stay street legal. Now I see all these High FLow Cats that say "Off Road only" "not street legal"....What's the purpose of having a cat if it's not street legal why not get away with it alltogether and run a straight pipe???

Having said that does anyone know a good street legal high flow cat for the z?

 

Hi flow cats enable you to pass emissions or i believe in CA they call them 'smog checks'. Whereas straight pipes/race pipes/cat delete's will not!! Also, straight pipes are known for making your exhaust alot louder and 'raspier', whereas hi flow's suppozedly tone down the volume a tad. But alot of ppl still complain that even hi flow cats are still loud!!

 

but it won't passed the stupid visual inspection in CA, so no, 99% it's not legal.

 

There are NO High Flow cats on the market that will pass smog. None of them are CARB LEAGAL on OBDII Cars...

 

Actually I have a CARB exempt OBDII High Flow Cat on my Celica right now...

But coming back to my question: Why have a high flow cat at all if it's not legal to begin with???

 

I know in those Random Technology ads in magazines I always saw the quote

"Removal or replacement of properly functioning original equipment catylitic converters is a violation of federal law."

Or something close to that.

 

Let me know the brand / model number and I can check for you to keep you out of trouble...

 

no idea anymore I picked it out at the muffler shop and checked the label and sticker. Jegs has several 50 street legal ones as well in their catalog.

Does no one have an answer to my question?????

 

I believe the law in California goes like this: you cannot replace the stock cat for any reason unless the stock cat gets destoyed or otherwise fails. Even then, you must replace it with another oem cat. If for some reason there are no longer oem cats available (such as when the manufacturer quits making them), only then can you use an aftermarket cat. At that point, the cat must be CARB certified.

I believe that's how it goes. As far as the actual testing, there are two parts: the actual smog test (where they check the emissions coming out the tail pipe), and the visual test. An aftermarket cat will pass the emissions test no problem since they are completely functional. However, you will not pass the visual test unless you get an inspector who simply fails to notice your aftermarket cats. (Sometimes their vision can be impaired with the proper "funding," but that's out of the scope of this discussion.)

It's a stupid law, but that's unfortunately what we have to live with here. A common option is for people to re-install their stock cats when it comes time to get a smog test. The cats aren't that hard to swap out and you'd only have to do it every few years, so lots of people go that route.

 

From what I have recently heard... there are no 50 state legal carb certified cats for OBD2 cars...

Ill find out more tommorow...

 

I hate to be the barrer of bad news...

According to the California Air Resources Board (C.A.R.B) They only have a hand full of approved OBD II Catalytic Converters...

(THIS IS GOING TO BE SOMETHING TO BOOK MARK)

If you dont feel like reading the details then all you need to do is read this next part...

Basicly the only CARB Approved OBDII Catalytic Converters are for the following vehicles:

Select GM Trucks & Certified to Low Emissions Vehicles.
2001 & Older Chrystler Trucks
Select Dodge / Jeep / Chrystler trucks, SUV, Vans
1998 and Older Mercedes-Benz & BMW Passnger Cars.
2002 and Older FORD Passenger Cards excluding vehicles equipped with a warm up catalyst.

So unless your NISSAN 350Z / Toyota or anything else you have. NO ONE has a "CARB APPROVED" cat for your car.

Manufacturers word it "50STATE CARB LEGAL Cat...." That may be true when that catalytic converter is in place on a GM Truck. But not when it is in place on a 350Z for example.

Unfortunatly this does not only apply to CATS but to any part that was OE Equipped on a vehicle and put on another vehicle etc etc...

Below are the specifics of what is approved by CARB for cats incase you are a GM / Benz / Chrystler / Ford owner...




Manufacturer: AirTek, Inc. (d.b.a. Catco)

Device: Series 712000 TWC
Device Type: OBD II Catalytic Converter

Part_Number: Series 712000_

Model_Specification: Selected GM trucks with dual parallel or single exhaust, certified to Low Emission Vehicle (LEV) or less stringent standards, excluding vehicles equipped with a warm-up catalyst._

Modification_Allowed: NONE

Remarks: Please contact the manufacturer or distributor for a catalog or the exact part number for a specific vehicle. Vehicle applications are specified in Appendix D-280-10 of the E.O._



Manufacturer Name: AirTek, Inc. (d.b.a. Catco)

Device: Series 712000 TWC

Device Type: OBD II Catalytic Converter

Part_Number: Series 712000
_
Model_Specification: 2001 and older Chrysler trucks with a single underbody catalytic converter, certified to Low Emission Vehicle (LEV) and less stringent standards, excluding vehicles equipped with a warm-up catalyst._

Modification_Allowed: NONE

Remarks: Please contact the manufacturer or distributor for a catalog or the exact part number for a specific vehicle._




Manufacturer Name: Car Sound Exhaust System, Inc.

Device: Series 43000 TWC

Device Type: OBD II Catalytic Converter

Part_Number: Series 43000_
Model_Specification: Selected GM trucks with dual parallel or single exhaust, certified to Low Emission Vehicle (LEV) or less stringent standards, excluding vehicles equipped with a warm-up catalyst._

Modification_Allowed: NONE

Remarks: Please contact the manufacturer for the exact part number for a specific vehicle. Vehicle applications are specified in Appendix A of the E.O._



Manufacturer Name: Car Sound Exhaust System, Inc.

Device: OBD II Compliant TWC

Device Type: OBD II Catalytic Converter

Part_Number: Series 43000

Model_Specification: Selected Dodge/Jeep/Chrysler trucks, SUV, and vans with single or dual parallel exhaust, and certified to Low Emission Vehicle (LEV) or less stringent standards excluding vehicles equipped with a warm-up catalyst._

Modification_Allowed: NONE

Remarks: Please contact the manufacturer or distributor for a catalog or the exact part number for a specific vehicle. See Appendix D-193-26 in the E.O. for specific vehicle applications._




Manufacturer Name: Miller Catalyzer Corporation

Device: 11000/12000 Series TWC

Device Type: OBD II Catalytic Converter

Part_Number: Series 11000 and 12000_

Model_Specification: 1998 and older model year Mercedes-Benz and BMW passenger cars. The Series 12000 TWC as front catalytic converter (2 units) and Series 11000 as rear catalytic converters (2 units) will be used in multiple catalytic convertersystems (4 units total) for Mercedes -Benz vehicles. Series 11000 will also be used for dual (2 units in parallel) or single (2 units in series) exhaust system applications for Mercedes-Benz vehicles. Furthermore, Series 11000 will be used for dual (2 units in parallel) and single (1 unit) exhaust applications for BMW vehicles, Catalytic converters for Mercedes-Benz vehicles will be sold as a complete system only, and not as individual units._

Modification_Allowed: NONE

Remarks: Please contact the manufacturer or distributor for a catalog or the exact part number for a specific vehicle._



Manufacturer Name: Walker Engineering Co.

Device: Series 200100 TWC

Device Type: OBD II Catalytic Converter

Part_Number: Series 200100

Model_Specification: Selected GM trucks with dual parallel or single exhaust, certified to Low Emission Vehicle (LEV) or less stringent standards, excluding vehicles equipped with a warm-up catalyst._

Modification_Allowed: NONE

Remarks: Please contact the manufacturer or distributor for exact part number for a specific vehicle. Vehicle applications are specified in Appendix A of the E.O._




Manufacturer Name: Walker Manufacturing Company

Device: Series 200200 & 200300 TWC

Device Type: OBD II Catalytic Converter

Part_Number: Series 200200 & 200300_

Model_Specification: Dual parallel underbody exhaust systems on 2002 and older Ford passenger cars, excluding vehicles equipped with a warm-up catalyst. Series 200200 is for front catalytic converter applications and Series 200300 is for rear catalytic converter applications._

Modification_Allowed: NONE

Remarks: Please contact the manufacturer or distributor for the exact part number for a specific vehicle. Vehicle applications are specified in Appendix A of the E.O._





Manufacturer Name: Walker Manufacturing Company

Device: Series 200100 TWC

Device Type: OBD II Catalytic Converter

Part_Number: Series 200100_

Model_Specification: Selected GM trucks with dual parallel or single exhaust system, certified to Low Emission Vehicle (LEV) or less stringent standards, excluding vehicles equipped with a warm-up catalyst._

Modification_Allowed: NONE

Remarks: Please contact the manufacturer or distributor for the exact part number for a specific vehicle. See Appendix D-182-33 of the E.O. for specific vehicle applications._



Manufacturer Name: Walker Manufacturing Company

Device: Series 200100 TWC

Device Type: OBD II Catalytic Converter

Part_Number: Series 200100

Model_Specification: 2001 and older model year Daimler-Chrysler Corporation trucks and vans certified to Transitional Low Emission Vehicle (TLEV) or less stringent standards and equipped with OBD II systems._

Modification_Allowed: NONE

Remarks: The exemption excludes vehicles certified to Low Emission Vehicle (LEV) standards and vehicles equipped with a warm-up catalyst. Please contact the manufacturer or distributor for the exact part number for a specific application._

 

An aftermarket part may pass on a sniffer... But if you do get an inspection and the part is on your car even if it is carb certified for another car, your car will fail...

 

Yeah, that's what I was saying up above. That's why I mentioned the "funding" part. Also, it's possible the inspector will not catch it. If you have an aftermarket cat that looks like an oem part, it might be overlooked. Granted, that is a risky way to go because if you get caught then you get fined. For what it's worth I've read numerous posts on other forums over the years for other types of cars where guys had aftermarket cats that looked relatively stock, and they passed their visuals just fine. If you have any of these fancy polished cats, though, you're guaranteed to fail. No oem cat is ever going to be polished.

 

The cat I have was not for a specific car I have a custom exhaust on the celi....but anyways.

I appreciate the thread about cat legalities but none of you have answered my question so here it is again:

Having a straight pipe vs a high flow cat will generate more power
I was under the understanding that a cat is required in order to stay legal in the emmissions range.

So why use a high flow cat at all if it is illegal, why not just go straight pipe? FYI: this is for off road use only

 

yeah so your high flow cat is not technically legal.


The high flow cat isnt as loud as a test pipe set up, and when you are behind a car with high flow cats you do not smell what you smell with test pipes. So you can get away with a high flow cat on highway use better then you can with test pipes..

 

Jason is right about the smell. Running test pipes makes you car smell bad from behind, and it's obvious to any cop that you're not running cats. If the cop is uptight about that (and many are) then he/she can pull you over and check it. I've never had it happen to me personally, but I have people tell me about it all the time.

Wait, now that I think of it, I was on the freeway this weekend and there was a guy in a slammed and modded car on the side of the road yesterday with a cop behind him. The guy had the hood open the cop was looking in it making notes on a pad of paper. I have no idea what was going on, but I can only assume the cop was checking for illegal mods. Of course, he couldn't have checked the cats on a Z while parked on the road (since they are under the car), but it's still something to think about.

I personally also like to run cats to help the environment. I'm not a crazy tree hugger or anything, but even a set of aftermarket high-flow cats reduces harmful emissions *significantly* over test pipes. Besides, unless you're running big forced induction, you probably won't see any significant power difference between high flow cats and test pipes. A couple of horsepower, maybe, but that simply won't make a difference in the real world.

 

I live in Louisiana they put some type of device where the fuel cap is located. What kind of test are they doing? They do not stick any testing equipment on the tail pipe.

 

Other states allow cat changes or no cats, California does not.
So places with hi flow cats for sale are technically catering to other states, it just so happens they will sell them to California residence anyway.

It's a big wide world, not everybody has to play by the same rules.

Chris

 

some cops do carry mirrors in their squad cars to check the undersides of cars.

 

How could they possibly tell if the CAT would be stock or not with a mirror???