Emissions time. Already got my extension which runs out next week.

Went to my dad's to reinstall my cat. Find out he recycled my cat for $20.
Pulled a cat off a stock 1.6 miata that was at the shop. Tried my damndest to make it fit. No chance.

Found a junk cat of unknown origin, removed the heatshield, and installed it around my test pipe. Convincing! Looked just like a cat. So I went to the testing station.
Results:
Reading Allowed
25/25
HC 143 160 pass
CO% .76 .90 pass
NOx 752 1179 pass
50/15
HC 149 166 pass
CO% 1.86 .93 FAIL
NOx 828 1304 pass

The tester says to me, "I think you need a new o2 sensor."

So I'll have to buy and install a cat.

 

Bum deal. BEGI is selling some ceramic ones for a decent price i think.

 

Take the stock cat you found, bring it to a muffler shop and have them make it fit the same location as your test pipe. Should be pretty cheap. I used to do this on my DSM, had a full 3" but when emission time came I'd pop in a stock cat with 3" flanges welded on.

 

Can't you just lean the **** out of it with MS and try again?

 

forgot to mention, that I retarded timing 10° from current

 

This looks like a winner to me:
http://cgi.ebay.com/ebaymotors/Carso...spagenameZWDVW
Can I MIG steel flanges to stainless?

 

Yeah you can. Muffler shops do it all the time consider many new OEM exhausts are stainless, they use all mild carbon steel parts though. It might not be pretty but it will work fine.

 

I dunno, MS says to lean the fuel in the manual here:

http://www.megamanual.com/v22manual/mtune.htm#emissions

But you're double the limit so I don't know if that would help enough to pass

 

Yes. Not quite as beautiful as a TIG'ed connection, but it'll work.

94106 is a good cat. In fact, I believe that is the exact same one that I've got on my car (from Tony).

 

cool, thanks Joe. I saw some other generic 2.5" cats, but this one was an actual name brand. I submitted an offer of $52 shipped, and the seller accepted.


glad that MIG will work. the other welds in my exhaust are ugly as sin, so it will be right at home.

 

Looks like requirements over here are a little bit more strict, here are the maximums that are listed on my last test for the '90:

15mph: HC=134ppm, CO=0.82%, NO=847ppm
25mph:HC=108ppm, CO=0.71%, NO=786ppm

last test was stock with 240k on the old engine and passed really well on CO, but had high NO. Next month im testing w/ new 3"cat, rebuilt motor, and megasquirt should be no problem.

 

Could you post a picture of your pseudo cat? I live in a location that only requires I have a cat in place, no test what so ever. I ran a test pipe, but got nailed and had to install a new cat to pass. I thought about gutting my present cat, but could not bring my self to destroying a brand new part. Camouflaging a “test pipe” sounds like a winner to me.

 

sucks, in my county in PA you're emissions exempt if you drive the car less than 5000 miles a year, so my way around emissions is to have enough vehicles to split the miles between

 

Milton, I'll get a pic next time I lift the car--I assure you, it's convincing.

Mach, I wish. My car would definately qualify.

 

Ben, to MIG mild to stainless, get some 309L wire. I think that's the "mis matched steels" wire.

 

My dad's welder uses the 'big' spools, at $60 a pop.
I will have to find a kind volunteer with a welder, or pay a muffler shop or something.

Uhm, what if I get SS flanges? Can I MIG SS to SS? They're the same price as mild flanges, it looks like.

 

Mr Tucker:

Any bad words about my weld in the forground = ban

 

That’s the **** (not the welds ) I am sure The inspectors would never notice the heat shield on the test pipe. As for the welds as long as part A is stuck to piece B who cares what it looks like?

 

you can totally mig stainless to stainless. You should really use pure argon though.

or maybe you can re-wind 309L onto a big spool...

 

dude my local mufler shop just turns up the power to weld stainless to mild. works fine. Mach couldn't you just lie and say you only drive 5K a year? Ben then welds are ugly but i assume they will work. GL with your testing