Is it legal to install a downpipe, say for example a 3" downpipe, if you have the right number of cats that a carb certified for pre obd2 cars.

What I want to do is take a stainless cheapo 3" ebay downpipe and put in 2 "high flow" metal cats of the right type, the first one is 3 way, the second is 3 way + air. They are carb certified OBD 1 replacments and EPA certified.

If other smog systems are functional it would obviously pass smog, but it should be completely legit right.

If that isn't legit then would it be legit to take the flange portion off the factory downpipe up to beyone where the O2 sensor goes, and cut that off, then port it out and weld a 3 inch downpipe connecting as above to 2 cats.

Don't post unless you actually know the awnser, I need something that is actually legal, I am going to the smog ref next month to ref my 13b-rew swapped FC.

I have a stock FD precat/downpipe but it hits the firewall on the FC, I can do some ghetto fab and angle it down, but I would rather do something better.

 

There is no way to make a legal piece of emissions equipment unless you go through all the red tape required to get a CARB EO#. It doesn't matter if that downpipe runs as clean or even cleaner than the stock pipe, if it doesn't have the EO#, it'll always be illegal.

 

It'll be legal until you get caught!

Who cares about emissions when you have WackyRacer. He'll help you pass that gross polluter of yours.

 

Thats just the thing,

Would it be making a piece of emmisions equipment?

The cats are emmisions equipment, and clearly you can replace those legaly providing you get the proper carb certified unit. Its OBD 1 so that means you can use a universal cat, not one certified for a particular vehicle as long as its a carb certified universal cat and the type matches and the displacment threshold is not exceeded. The cats will allready have an EO# that makes them legal for pre OBD2 cars up to a certain displacment.

Someone is going to say that thats just like a header but its not.

In any case I have the Smog Manual on order, hopefully I will get it soon, at which point maybee the question can be more easily awnsered.

 

Please keep this crap out of my thread...

 

Look at the emissions equipment label under your hood. I know it says TWC for three way catalytic converter. I'm not sure if it lists the pre-cat though, and if not, it's completely legal to put a downpipe in. Honestly, no cop or smog guy is going to go through the trouble to make sure you have a precat, since it's not really viewable from the engine bay.

Weld in the largest hi flow metallic cat that you can find in place of the stock cat. If you weld in an OBDII cat which uses Serium, it works without the need for an airpump. You can't pass smog without the airpump in place, but they'll never know that it pumps air to the atmosphere.

Our cars run so rich though that you'll either melt or coat the honey combs and by the time it's your next smog, the cat will be less efficient and might not even pass.

 

actually ca law does specificly forbid consolodating cats, that is replacing 2 cats with one, and the pre-cat is a 3 way metal cat. What I am talking about doing is starting with an FD aftermarket downpipe and welding in 2 carb certified OBD1 cats, one to take the place of the pre-cat using a 3 way metal cat, the second to take the place of the main-cat using a 3 way metal cat+oxidation. both cats would be carb certified up to well beyond the GVWR and displacment of the vehicle. And would be the same type as the cats they are replacing. Again its obd1 so they don't need to be vehicle specific certified. That is they can be universal.

 

This thread is already crap.

 

lol

 

seriously this is imature and old, I am asking a legit question and your whoring up my thread with useless posts.

 

If you really wanted a legitimate response, you would have posted this thread in the 3rd Gen Specific area. Everyone knows that anything goes in the West Section. Yes, you do have a right to post this thread here but it’ll get whored up. Lighten up dude it’s freakin Friday for crying out loud.

 

I think DJDino is a cry baby.

 

Wacky,

We are discussing a very imperative topic. It is counterproductive when you post such idiotic comments.

 

 

Alright guys, knock it off. Slo is actually trying to get info that keep the car somewhat legal. Take it to the SoCal postwhore thread. Seriously. Thanks.

 

You can still pass the emissions part of smog without the downpipe cat. You might fail visual but there is another main cat that cleans the exhaust. The precat gets clogged all the time making the engine run bad and give off worse emisions so people always go with a downpipe. But yeah, it isn't technically legal to run without a pre-cat.