Went down to the local smog station and TRIED to pass smog with my high flow metal substrate. Passed 2 years ago with stock cat with the same mods, so I expected to fail, but not by much. So the test completes and of course I failed, but only by the slightest of margins in the NO reading at 15mph. Max allowed at 15mph is 709, mine read 739. However at 25mph Max is 738 and mine only read 176. Suprising what a 4" little cat can do.

It's gonna cost me $80 to take of and put back on my cat. Do you think I can just put in some denatured alcohol and it will change the reading of NO? The tech said it would only change Carbon and hydrocarbon but not NO. What do you guys think?

 

Do you think that if you were to install an airpump fitting, it would pass??

 

Wow thats the news a lot of people have been waiting for. I wonder since Cali is the strictest would the car have passed in other States?

 

I would liek to know as well, I guess I will call my local state inspector.

BTW did you have the airpump or no airpump?

 

slip the guy a 100 dollar bill

 

Did you pass visual?

 

Which brand of cat did you use? Was your air-pump hooked up? I would think that a little denatured alcohol (1/4 gallon in 1/2 tank of gas) would do the trick given how close you are.

 

Air pump is installed and it is a random technology cat, only 4 inches long with custom pipes and fittings. Only $250 for the cat, install was pricey but worth it. Night and day difference. Buy the way, denatured alcohol is damn expensive. I was told it was $8 a gallon, now it's $12 at home depot. $24 to pass better then $80 to uninstall and install stock cat. Let you guys know how it does.

 

Reinstalling your stock cat is free! Do it yourself, its really easy.

 

Wait when you said 4 inch were you talking about the diameter?

 

Yes, the metallic substrate cats are usually 4" diameter with 2"-3" inlet/outlets available.

 

Good to hear!

I am just ordering my new 4" metal substrate (4" in and out...larger version) from www.smb.net.au including the complete exhaust system. (upgraded to 3.5") I will post pics in a few weeks...and also the dyno difference...might even get some .wav files...

Should pass the australian EPA without a drama if yours almost passed californian tests!

 

4" diameter, 3" in and out, 9.5" length....http://www.martelbrothers.com/custom...cat=550&page=4

I used to have the old random tech with ceramic substrate on a turbo GSR and it blew out with that low of an exhaust temp, this metal substrate should hold up to the FD heat

 

I'd still rather pay $20 or less to just pour in something then to actually get under my car and wrench, call me lazy

 

Did you change your motor oil, spark plugs, or spark plug wires prior to testing?

 

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/got-my-smb-metallic-cat-today-pics-421894/

 

If I remember right from all my emissions crap here in AZ the denatured alcohol had very little effect on NOx. It helped quite a bit for CO and HC as your tech said but I think NOx actually went up a little with alcohol.

I believe NOx is related to how lean you are, more lean is more NOx.

 

what kind of mods do you have?

 

Hey Tom, wouldn't adding alcohol make it run more rich because you are adding a more combustable fuel? That would make NO go down?

Can anyone else confirm this?

 

Mods include M2 airbox, M2 downpipe, racing beat exhaust, M2 ECU and high flow cat

 

Oh yeah, forgot the M2 large intercooler

 

I second the new spark plug advice. Also run the car hard before taking to test and have them test it before it cools. I would do this and try again as the emmissions tests i've seen can vary quite a bit from one time to the next.

 

I'm gonna go in Monday morning and retest with the alcohol. I'm at near an empty tank. Fill in a couple gallons with a gallon of the alcohol?

 

good info

 

http://www.zeroglabs.com/rx7/emissions.htm