3rd Catalytic(Cat) Converter Deletion Smog Results

J

OCCUPY LoD :)
Hey, I thought I'd start a new post for information purposes vs. hi-J-acking.

I've smogged mine twice with no third cat(and no resonator/mufflers). The second time I smogged it was January this year, with all the other upgrades.

Screamon Deamons
Nology's
3200 STall
Gears
Chip
K&N

but it was before my headers/exhaust work. Not that all that stuff matters, but you'd think it would do something :love-it:

Here is my first smog before my 3rd cat was deleted.

Smog1.jpg


Here is the most recent test on January 20th 2007.

Smog2.jpg


I just noticed the RPM differences from the first test(some random smog station) and the last test(my buddies smog place). I remember him mentioning that he keeps the rpms at the high side of the allowance to keep the cats nice and hot, so maybe it would fail, but regardless its still not close to the allowances.
 
Wow it slides by pretty close on the NO and some pretty huge differences on the O2. Maybe those treehuggers are on to something :). It may have something to do with the fact that your old cats had 150k miles on em.
 
J, California dose not test for NOX?
EDIT:Ok I see the NOX (PPM)
This is my test done last year when my car was stock.

1727.jpg
 
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Your car measured lower than mine stock....I'd think it'd pass fine without the 3rd cat.
 
I just noticed the RPM differences from the first test(some random smog station) and the last test(my buddies smog place). I remember him mentioning that he keeps the rpms at the high side of the allowance to keep the cats nice and hot, so maybe it would fail, but regardless its still not close to the allowances.

Your rpms are up also because of the higher stall converter.

When I got mine tested, the guy asked me if I had an aftermarket converter in it...he knew it wasn't stock.
 
My sticker is up this month.So I need to get it tested.

Glen, you shouldn't have any problems since you have the Magnaflow 3rd cat. BTW, did you notice any gains at the track from your exhaust setup? I can't say that I did but then again the DA was higher and the headwind was crucial.
 
Your rpms are up also because of the higher stall converter.

Good point, I didn't even think of that. My smog tech buddy also does a "trick" when smogging all my vehicles. He'll run the car up to the max allowed speed per test and slowely come back down.....never fails :) Thats what I was thinking caused such high rpms.
 
FWIW:
My car failed miserably on NOX without the third cat which is a "Nox scrubber".

Glenn might not have any problems, because his cat that he bought SHOULD include a NOX scrubber.

he and I are in the same county, so the test limits are the same.
 
FWIW:
My car failed miserably on NOX without the third cat which is a "Nox scrubber".

Glenn might not have any problems, because his cat that he bought SHOULD include a NOX scrubber.

he and I are in the same county, so the test limits are the same.

I noticed in another post that you had problems with your EGR system. EGR reduces NOX too.

Maybe it's time to replace that DPFE sensor?;)
 
Dangit... stop being right all the time!
(JK)
*seriously*
You are correct.. I do need to swap the DPFE.
contemplated doing it along with the EGR valve and tube when I had the motor out..
"STILL KICKING MYSELF" on that bad decision.
 
The DPFE sensor is easy to replace with the engine in the car, compared to the EGR tube.

I know this because I've done both.:)
 
Thanks, I'll probably chunk one at it here pretty soon.
Thanks for the tip, after looking at it and knowing how it's all laid out, I dont think it will be as bad as if I tried to "feel around" and figure out how to get it out of there.
 
That is what I said above, I've already seen how it's held on the motor and where the vacuum lines go so I wont HAVE to "feel around".

BUT.. thanks for the picture it will help myself and anyone else who happens across this thread
 
A tip for working on the DPFE sensor or EGR tube:

Disconnect the hood struts so you can open the hood wider and prop it up with a broom stick or something. It's much easier to see and work back there then.

Be careful not to raise the hood too much though, the corners will eventually touch the cowl area.

I don't remember if I had to remove the wiper motor for the DPFE sensor, but I did for the EGR tube.
 
Good advise Bill :) An added tip for removing the EGR tube from the factory manifold....sawsall, lol! Mine was broke but still prevented me from removing my manifold to install the headers.
 
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