catalytic converter

[GreenBeam]

Could a catalytic converter be the answer to getting a 76 2002 to pass smog?

[keninmorganhill]

Green..

"It'll CERTAINLY help."

I've had nothing but '76's and have always had to deal with the Smog bit. Have all of the Smog Equipment on you car for sure.. AND.. do the Catalytic Converter thingy.

I'm here in California where we have to deal with that stuff constantly.

"It DOES work."

Ping me if ya' need anymore info.

- Ken (ralphus29@yahoo.com)

[GreenBeam]

Thank you. Thats really comforting to know. Just finished reading a thread leaving me thinking that I was running out of options with this car. But I'll definitely contact you if I run into any issues regarding smog.

[oldguy]

depends on placement and type...

Aftermarket ones have a long time to light off.. If you've got some type of airpump system on the car that's key in getting them to light off.

A precat of a modern car maybe more helpfull and you could attach it right after the manifold and it would light off quick.

I don't know if they make you perform the test warm or cold. If you can try the smog test warm with the cats all warmed up then go for it. Hot rod did an article showing most modern aftermarket cats take about 2-3HP out of an engine. They've come a long way.

[Guest Anonymous]

Something's wrong with your car.

You have a relatively small engine. A properly tuned 4cyl is easy to get through compared to a 400+ cubic inch GM monster of the same vintage.

[BarryA]

come with one when it was new, but be aware that the CA ARB is making the purchase and installation of anything OTHER than OBD II cats difficult (if not impossible) in CA for cars that came with cats new. Wouldn't be a big deal except that OBD II cats have to meet much tougher warrantee requirements, and as a result are much, MUCH more expensive than OBD I units.

My E21 barely passed smog this fall, and I expect to have to replace the cat for the next testing cycle in two years - the last cat I bought for it was about $180 installed 3 years ago. If I had to install an equivalent OBD II cat today, the cost would be at least $800 - with higher sales volume, I'm hoping that OBD II units may come down a bit , and I'm also going to check into getting a universal OBD I unit installed over in Reno as well.

[BMWonly]

My E21 barely passed smog this fall, and I expect to have to replace the cat for the next testing cycle in two years - the last cat I bought for it was about $180 installed 3 years ago. If I had to install an equivalent OBD II cat today, the cost would be at least $800 - with higher sales volume, I'm hoping that OBD II units may come down a bit , and I'm also going to check into getting a universal OBD I unit installed over in Reno as well.

Barry, I bought an aftermarket cat for an E21 320i in May 2009, it cost me $322 installed with a generous warranty (which is required in CA). I assume the same cat could be installed on any M10, and should work for a 76 2002.

Dieter

[Richard]

Do you have the failure graphs??? Whats failing??? Are all the emisson equipment there??? To be honest the car tuned really well would pass without emisson stuff.... I have to disagree on the cat. Locate the problem

[socalsean]

My car didn't pass at first. Something about the previous owner messing with the jets in the carb. I welded a Volvo 240 cat near the tranny and it passed!

[PeterVarga]

What I hear about CAT....

1. A cat that is near the manifold (ie. replaces the down pipes) would heat properly....essential for the cat activity....someone is working on this....making a cat that fits in place of the down pipes.

2. If your '02 has air injection, since most cats increase the back pressure of the exhaust theyt lower the efficency of the air pump system. This could increase (!) the unburned hydrocarbon readings.

3. A cat mainly reduces unburned hydrocarbons, I have been told. Therefore if at the same time you reduce the effectiveness of the air injection system and at the same time increase the burning of unburned hyrdocarbons with a CAT you may null each other out in the smog calculation. (They're testing this I have been told.)

4. There is a manufacturer of CAT converters that has a very low back pressure. This is going to be the recommended converter for installation on '02's. More on this if I find out what company makes these and if they are going to be sold.

In sum, a low back pressure CAT mounted near the exit of the hot exhaust gasses, ie., at the manifold, may help reduce HC emissions. Whether is reduces them more than the impeded air injection system does is up for grabs.

If your car is failing smog you first have to comb through the major systems and make sure they are in order. Start with the carb as the other poster said and follow the jetting prescription the poster CD repeatedly posts. And then proceed to valve settings, timing, distributor advance and the other systems that your car should have. It'll probably pass without the CAT if everything is set properly!

[PeteinMissionViejo]

I bought a cat on E Bay and had to have it shipped to Az. then brought to me. Probably the same kind of cat I had purchased previously but they stiffened up the laws at the start of 09. Not for a BMW

Pete