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failed emissions question No flaming please...

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Old Mar 8, 2012 | 04:57 PM
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failed emissions question No flaming please...

I am selling my car and figured why not bring it up the street and see how it does for 20 bucks before I get rid of it. I tweaked my tune, no cats or air pump and a few bottles of HEET. Well it failed as expected but I am not an expert on the HC, CO, NOx results.

Passed the NOx with 277ppm allowed 2692ppm
Failed the CO with 3.21% allowed 1.23%
Failed the HC with 597ppm allowed 231ppm

Does anyone think that I can get it to pass with just a catted midpipe and no air pump??

single turbo
PFC
550/1600
9plugs all around
etc...

Thanks,

Doug
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Old Mar 8, 2012 | 05:08 PM
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You're going to need a cat, no bones about it. And an air pump will help greatly. You can wire up an electric air pump from a late model GM car for relatively little money, and it will be easy to install and remove.

I like to use this chart to aid in emissions, too:

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Old Mar 8, 2012 | 05:46 PM
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From: https://www2.mazda.com/en/100th/
i've lived in CA my whole life, and i smog about 4-6 Rx7's a year and here are my findings. CA standards are very tight, so we need the air pump and cat to pass. the air pump air must go to what mazda calls port air. if you're allowed 230ppm of HC and 1.2 CO @2600rpm then with the air pump, you may not even need a cat, or vice versa. in CA we get 90 HC's and maybe .4 CO with 300NOX? stock FC's with OPERATIONAL air control valves pass this no problem.

the mixture effects the rotary in the same way as a piston engine, leaner than 14.7:1 lowers HC and CO until it misfires and then they go way up. NOX goes up as you lean it out.

timing has almost no impact on HC or CO, but advancing it will raise NOX a little.
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Old Mar 8, 2012 | 07:35 PM
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From: cold
listen to the voice of experience ^
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Old Mar 9, 2012 | 06:17 AM
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From: oslo/ norway
you could try to mix 50/50 gasoline and e85. and try again.. but don`t drive it hard ore you will lean out..
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Old Mar 14, 2012 | 01:42 AM
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Originally Posted by Boxer2rotary
I am selling my car and figured why not bring it up the street and see how it does for 20 bucks before I get rid of it. I tweaked my tune, no cats or air pump and a few bottles of HEET. Well it failed as expected but I am not an expert on the HC, CO, NOx results.

Passed the NOx with 277ppm allowed 2692ppm
Failed the CO with 3.21% allowed 1.23%
Failed the HC with 597ppm allowed 231ppm

Does anyone think that I can get it to pass with just a catted midpipe and no air pump??

single turbo
PFC
550/1600
9plugs all around
etc...

Thanks,

Doug


Heat that them CAT's up!! Your actually closer than you think to passing..
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Old Mar 14, 2012 | 09:27 PM
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Originally Posted by abc
Heat that them CAT's up!! Your actually closer than you think to passing..
How long should I drive on a new CAT until its heated good enough??

BTW I did have 5 bottles of HEET in a 1/4 tank and drove really easy lol.

I am grabbing a 3" magnaflow carb approved cat off ebay and I am gonna make a couple v band flanges so I can swap it on and off the existing mid pipe. I think I will try just the cat and go from there since the second time is free.

Thanks for the advice.
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Old Mar 15, 2012 | 11:57 PM
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I normally take mines for a 20 mile hwy ride. G/L keep us posted
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