i want to get 1 of 2 ideas that i have for my exhaust setup. but my question is if i have a problem passing smog with either setup, would it not be possible to put more then one cat on there to make it pass. if one cat is good 2...or 3 must be better right? i dunno if this would actually make a difference but if it did could i not just have a section of my exhaust removable so i can have a 1, or 2 cat pipe put in during smog to make it pass then once i've pass i can take it out and put a straight pipe. i have no idea if this concept of more then one cat will clean better than 1 but does anyone know if this might make a difference. (go ahead and laugh if you think my idea is dumb but i'm desperate to get away with what i can) haha

 

cats need to be a certain temp to work right, putting more than one on or a bigger than needed will casue a efficiency problem, meaning they will not burn off the emissions like they should. i dont know about the smog laws in your state but i do know them in california, and id fail your car in a heartbeat and send you to the refferee (which is not good).

now sure a test pipe could be used in place of certain equipment, and be removed when needed for actual testing

 

yeah you're right about the temp thing. i live in concord NC and they arnt "too too" strict but they still do the sniffer test which i've heard rumors that NC is gonna do away with sniffing for 95 n older models but no one knows for sure. but either way, i still need to do something for now. the 2 ideas i was thinking of were:

1. headers (?long tube?/?short tube?) to a 3 inch y pipe, hollow cat, and a glass pack with a 2 1/2 turn down before the rear axle.

2. headers (?long tube?/?short tube?) to a 3 inch y pipe, hollow cat, and an 80 series flowmaster with dual 2 1/2 inch pipes coming out the back

?!?!?!?!?!?!?!?! now i'm certain that with either of these setups there's no way i can pass the sniffer test around here which is where the idea where i would remove the section of the hollow cat and place a real cat came from. anyone have any suggestions as to which idea they like best and what you think of my cat swapping idea

 

Dunno about the multiple cats, but people do the swapping here all the time. Change for the test and change back that afternoon. I had friends in highschool do that. No biggie at all. If you need to pass, run octane booster, it runs you cleaner and get an adj fuel pres regulator. (to lower pressure). Have a cat, and air tubes. Don't worry if you have headers. i have passed with shorties just fine. The exhasust is still the same stuff in those tubes as in the manifolds.

Hope some of this helps.

 

you know thats a great idea. i'm glad you said that. i'm gonna go with the headers anyways because i'm stubborn and thats what i want but as far as the octane thats a great idea. and i was gonna put an adj. fuel pressure regulator on there eventually but i wouldnt have thought to lower it for the inspection. thanx for the advice

 

the old emissions test. I think your best bet is to use high flow cats and Gaurenteed to Pass or some other off the shelf product designed to clean emissions. This stuff is like glorified injector cleaner might just be the same thing but it works great. I know about 10 people that have passed with it after failling without it. I know one guy that passed california with a malfunctioning 84 fiero and a bottle of this stuff and the guy said it was the cleanest readout of any car he had seen. One freind of mine upon reccomendation from a chemical engineer put a $5 quart of xylene from the hardware store and a full tank of premium in a supercharged 5.0 stang with two highlow cats and he was cleaner out of the tailpipe than before the blower was installed. Put the fuel treatment in the car and go for a long highway drive 1/2 a tank or so to allow it time to work. the hotter the better with cats. so take your test right off of the highway if you can.
Just one cat will do. Thats what they are made for. Some cars like mustangs have 4 but they are small. I think it is an issue of gas temp. They can be found for about $50 new on ebay for a 3" and they work fine.
I personally think the hollow cat idea is a waste of time. If you hollow one out you then have to put a pipe through it or it will flow like crap. The old take the cats off mentality was from the early days of cats. Like anything else technology has improved and the modern day high flows migh cost you a horse or two. Not to mention cleaning the
air a bit is not the worst thing we could do.

as far as the afpr is concerned the ecm will adjust for slight changes in fuel pressure unless you turn it down so low that it is out of the computers range of adjustment. this would not be helpful if your state tests for oxides of nitrogen because the leaner hotter combustion chamber will create more of these gases especially with on cars with no EGR. The pressure regulator makes more of a difference on quick stabs of the throttle not at steady cruise or idle like the test will be.

hope this helps sorry for the long post

 

[QUOTE]Originally posted by AUTOGON350
the old emissions test. I think your best bet is to use high flow cats and Gaurenteed to Pass or some other off the shelf product designed to clean emissions. This stuff is like glorified injector cleaner might just be the same thing but it works great. I know about 10 people that have passed with it after failling without it. I know one guy that passed california with a malfunctioning 84 fiero and a bottle of this stuff and the guy said it was the cleanest readout of any car he had seen. One freind of mine upon reccomendation from a chemical engineer put a $5 quart of xylene from the hardware store and a full tank of premium in a supercharged 5.0 stang with two highlow cats and he was cleaner out of the tailpipe than before the blower was installed. Put the fuel treatment in the car and go for a long highway drive 1/2 a tank or so to allow it time to work. the hotter the better with cats. so take your test right off of the highway if you can.
Just one cat will do. Thats what they are made for. Some cars like mustangs have 4 but they are small. I think it is an issue of gas temp. They can be found for about $50 new on ebay for a 3" and they work fine. [QUOTE]

do you know the name of this "glorified injector cleaner" or can you find out for me i would be forever greatful. and what is this xylene stuff? will it damage anything on your car?

 

The stuff that I just used was from a company called BARDAHL the product is called ALL-U-NEED. They will give you twice your money back if you fail.
There is also a product called -Guarenteed to Pass- I have heard good things about it as well.
My uncle used this stuff from www.blueskycleanair.com in California. He passed with an 84 that was not working right.

Most of these can be found at parts stores nationwide I thought.

As far as the xylene is concerned it is just a solvent like paint thinner. You can buy it at the hardware store. We use it at work to wipe stuff down before we paint it. My friends dad is a chemical engineer and told us that all we needed was to put xylene in the tank and the cars should pass. For all I know that could be all thats in those injector cleaner emissions fuel treatments. This guy is a chem expert but not a motorhead. I cant gaurentee that this wont hurt anything but it was his educated opinion. One friend of mine tried it with his blown stang and it passed just fine. No problems have resulted as far as we can tell. Post a question about it perhaps someone can shed some more light on it. I got a D in chemistry.

If your car is in really bad condition there is probably nothing you can do to pass but if it is working somewhat corectly and just needs a little help the fuel treatments should work. Your best bet is to get in good with someone at the DMV and they can just give you plates

good luck

 

i am forgetting the specifics but you actually have less emmisions with lower octane then with higher

it's wifes-tale so to speak that higher octance helps you pass, and higher octane helps you get cleaner injectors with fuel injection cleaner.

 

well all this information helped. but my car isnt nessasarily running badly, its just with the mods i want to do it wont be street legal occording to smog. well i do appreciate all your help. i guess the real test will be to do the mods and try out some of this stuff...

 

It seems that there are a lot of mods that are not street legal technically but should not hurt come inspection time. The manufacturers cant make everything street legal because it would be really expensive for them to do so and almost impossible.
For a third gen to be street legal BY THE BOOK you would need air tubes on the headers, egr, a stock air intake tube and filter, pcv valves on both valve covers, and lots of other original equiptment.
In my state you get the safety and emissions at two different places. If the car runs alright the guy doing the safety will probably not care if your exhaust system does not have A.I.R. tubes or you have pcv breathers and stuff like that. If a car fails at the emissions check place then they will visually inspect it and make you change stuff but a lot of the people I have run into dont know every last detail about what car should have what equiptment. Bottom line is dont try to pass a car with open headers and a carb and drag slicks if it supposed to be TPI. Obvious stuff like that. I know a lot of people that did just fine including myself without egr, and air systems hooked up. I even passed without mufflers once. Most of the time at least in the case of injected cars if the car is running well they only care about what comes out of the tailpipe. Thats how my friends astro van with the small block made it thru.

 

Stock, there's only one. The other cover has an air inlet to the air intake.

 

you got me. It has been quite a while since I looked at a stock one. I was just trying to illustrate the point that there is a lot of stuff that does not qualify as emissions legal but probably would not fail a car. What I should have said is that even one of those open element breathers on a valve cover would not be by the book but I think it would take a real picky inspector to fail it.

 

Not in Kalifornia.

Colorado would fail you as well.

 

well here in NC they arnt too strict, besides they are doing away with emissions laws as of 06 for all OBDI cars (95+ older)