Yes I'm putting this in the Tech. section. Why you may ask? Because I came across a difference in cats today.

So, what is the difference?

Well first off, I was going to get a new cat at Autozone. They have it in stock, and I need to pass emissions. I noticed it was labeled pre '95 OBD-I. Walker Part #15038

Now the question and possible problem.

What it the difference between an OBD-I and OBD-II cat? Can I use this cat that is labeled as OBD-I? Will it work without causing problems?

Physically they are the same. TECHNICALLY there must be some kind of difference, right?

Any insight would be nice. I'd like to get this thing done and passed tomorrow.

Thanks in Advance.

 

Maybe the OBD2 one has a bung for downstream O2 sensor? Thats the only difference I know of between the OBD1 and 2 as far as the cat is concerned.

 

That's the only thing I could come up with also. I tried Google but that didn't provide a damn thing.

I don't know if the metals inside are different, which you would think its all universal now, except maybe CA., if that was the case.

 

Well, can probably close this thread. I was looking around and found a Catco cat at Summit Racing for $45. Good enough for me.

I'll just go down there and pick it up in the a.m.!!

BTW, I have yet to find the difference though. Ehh well.

 

I wonder if the amount or type of catalyst is different. I recall some change in emission standard around that time, but I cannot remember the specifics.

 

Don't know. Maybe this should be left open then. Maybe someone will come around that knows.

 

A Walker # 15038 is wrong anyway. It only has a 2.5" inlet/outlet. IIRC, You need a cat with a 3" inlet 2.5" outlet.

 

Right. I ended up getting a Catco 6906 from Summit Racing. It also has 2.5" in/out. I just got a 3"-2.5" reducer and welded it up.

Now to see if it'll pass the B.S. emissions.