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SwiftTech
01-05-2006, 12:40 PM
Just failed emissions test. This was in my 1984 Daytona with turbo1 DC Intercooler kit, +20's @25pis static fuel Pressure. Readings were as follows:

Co2%: 15mph 14.5 25mph 14.6
O2%: 15mph 0.0 25mph 0.0
HC(ppm):15mph 91 (141max) 25mph 81(116max)
CO%: 15mph 1.15(0.86max) 25mph 1.18(0.66max)
NO(ppm):15mph 674(1161max) 25mph 467(991max)

It only failed on the CO. I'm thinking it needs an O2 sensor and mabey a cat converter. I did run leaded 110octane fuel once or twice through it last year so mabey I killed them both with that. What do you guys with Smog experience think?

Clay
01-05-2006, 12:47 PM
I would say your cat is fine cause it looks like its doing its job. Your HC are in check, which is they act on the most.

Looks like just a touch less fuel would put you in the zone. Your not that far off.

clay

turbovanmanČ
01-05-2006, 01:14 PM
I do emissions for a living and your too rich. I would turn down the fuel some more or install stock injectors for the test. How's your oxygen sensor? Can't tell if the cat is working, readings are all too high and NOX is low because your rich.

Clay
01-05-2006, 02:13 PM
I do emissions for a living and your too rich.

Oh so your one of those evil commies!

Now things make more sence!!! :p

SwiftTech
01-05-2006, 02:24 PM
so the +20's are rich even with the fuel pressure aty 25psi with the vac line disconnected? well I put a new o2 sensor in last night, so mabey that will help, but I think I might just get a new cat anyway, the one on it right now is a catco and it is at least 3 yesrs old. Now is a good time to step up to 3" exhaust I think.

altered7151
01-05-2006, 02:39 PM
The 3" with that header ought to get you into the 13's for sure Luke, I'd do it! But it does look like you're running too rich, you might not be getting a good fuel spray at that low of a fuel pressure either, which would make it appear to run rich.

Clay
01-05-2006, 02:43 PM
Granted, a cat kinda screws up this thinking, BUT ANYWAY!!

think of it this way, you have quite a bit of HC coming out of the exhaust, and absolutely zero oxygen.

Your using up all the O2, and have lots of HC left = rich.

clay

turbovanmanČ
01-05-2006, 05:39 PM
so the +20's are rich even with the fuel pressure aty 25psi with the vac line disconnected? well I put a new o2 sensor in last night, so mabey that will help, but I think I might just get a new cat anyway, the one on it right now is a catco and it is at least 3 yesrs old. Now is a good time to step up to 3" exhaust I think.

Don't replace the cat until you get the fuel mixture figured out, or you could damage it.

I have tested injectors down to 20 psi and still a good spray pattern but you need to go smaller for the injector.

SwiftTech
01-05-2006, 07:52 PM
I'll have to dig out the t2 injectors I have floating around then. I don't have t1 injectors anymore.

Thanks all!

mech1nxh
01-08-2006, 08:14 AM
I'll have to dig out the t2 injectors I have floating around then. I don't have t1 injectors anymore.

Thanks all!

p.m. sent ......
I am close to you and am one of those SMOG COMMIES ALSO(LOL)
C.A. unlimited SMOG license..(15 yrs or so)....

Tim
01-08-2006, 10:19 AM
The best cat is NO cat!

Just turn the fuel pressure down to 21-22 psi for the test and then put it back.

GLHSKEN
01-08-2006, 10:43 AM
The best cat is NO cat!

Just turn the fuel pressure down to 21-22 psi for the test and then put it back.


Not in California.....

deuce dodge
01-09-2006, 08:47 AM
oh MICHIGAN I LOVE YOU..no sniffers or visual........

deuce

MVaughn
01-11-2006, 12:06 AM
Whats a cat?

turbovanmanČ
01-11-2006, 02:49 AM
Whats a cat?


You serious?

If so, catalytic converter, its slang, if not, :lol:

Clay
01-11-2006, 09:07 AM
Whats a cat?

http://blog.lauralemay.com/files/2004/8/27/elsa.27733.jpg

Tony Hanna
01-11-2006, 09:36 AM
^ :lol:
Now I know why I get those wierd looks when I mention gutting a cat in mixed company.:p

turbovanmanČ
01-11-2006, 01:08 PM
^ :lol:
Now I know why I get those wierd looks when I mention gutting a cat in mixed company.:p


Also don't mention cat around asians, mmmmmmm dinner, :thumb:

Tony Hanna
01-11-2006, 11:20 PM
:lol:
I just keep telling my self "the health department wouldn't let it happen".
I guess I've convinced myself since I'll still eat Chinese every once in awhile.;)

MVaughn
01-11-2006, 11:40 PM
You serious?

If so, catalytic converter, its slang, if not, :lol:


Simon.....what am I going to do with you? :D

turbovanmanČ
01-12-2006, 02:36 AM
Simon.....what am I going to do with you? :D

Hahahha :lol:

Sarcasm is hard to pick up on the net with no smilies though, :eyebrows: :nod: :bolt:

SwiftTech
01-17-2006, 12:12 AM
okay I popped the t2 injectors back in it. Had to spend a good hour making a new injector harness as the old one was stiff and brittle as could be. I was lucky enoug to find the connector pins for the injector connectors at work but I had to reuse the flat blade ones at the 6 way connector. It turned out good though. I'll have to take a few pics. Anyway I digress, I fired the motor up and noticed it runs a heck of a lot smoother than before but sounds funny on reving it. It sounded like a dead cyl to me and I traced it to #1 cyl. I pulled the spark plug cable off the plug and the motor doesn't even stumble. I'll look into that more tomorrow. I've run out of light.

One more thing. I was doing some reading and I noticed compression can effect the emmisions. A while back I did a compression test and all cyl were around 95-100psi with no leakdown(2%). Could this be causing any problems for me?

turbovanmanČ
01-17-2006, 01:47 AM
okay I popped the t2 injectors back in it. Had to spend a good hour making a new injector harness as the old one was stiff and brittle as could be. I was lucky enoug to find the connector pins for the injector connectors at work but I had to reuse the flat blade ones at the 6 way connector. It turned out good though. I'll have to take a few pics. Anyway I digress, I fired the motor up and noticed it runs a heck of a lot smoother than before but sounds funny on reving it. It sounded like a dead cyl to me and I traced it to #1 cyl. I pulled the spark plug cable off the plug and the motor doesn't even stumble. I'll look into that more tomorrow. I've run out of light.

One more thing. I was doing some reading and I noticed compression can effect the emmisions. A while back I did a compression test and all cyl were around 95-100psi with no leakdown(2%). Could this be causing any problems for me?

Low compression can affect readings yes but your results don't jive with the leakdown test. You should have around 140 ish, you better recheck your cam timing. Whats your idle vacuum?

SwiftTech
01-17-2006, 02:08 AM
The guage points right at the corner of the stock boost guage. The last time I had the autometer hooked up to it I had around 12ish inches. A little low I know. But I did double check the cam timing a little bit back and it was dead on. ??? I think once I get the dead cyl back I'll take it for a retest and see how it does. The injectors and new o2 sensor will hopefully get it down to a passing level.

SwiftTech
01-26-2006, 06:22 PM
Well I took it to get smogged again today and it passed, just barely though. Reading were (15mph first 25mph second):
Co2%: 14.5 14.9
O2%: 0.2 0.2
HC(ppm): 111(141max) 72(116max)
CO(%):0.84(0.86max) 0.42(0.66max)
NO(ppm):344(1161max) 501(991max)

This was with t2 put in and two bottles of 91% isopropyl alcohol added to half a tank.

Clay
01-26-2006, 10:59 PM
Good deal!!