Emissions
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
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From: Dallas TX
Emissions
Ok, so what is the best way to pass emissions? I know that having the car hot is best and that it being tuned right does the majority of it. Does correct tuning mean that it's burning all of the hydrocarbon's or what?
I don't know much about emissions and Collin County is starting them in May (which is the date of my inspection). I might try to see if I can have it done early claiming that I won't be able to come back to the state for a while because of school or some other :bs :jester
I don't know much about emissions and Collin County is starting them in May (which is the date of my inspection). I might try to see if I can have it done early claiming that I won't be able to come back to the state for a while because of school or some other :bs :jester
Melting Slicks
Joined: Apr 2001
Posts: 2,074
Likes: 206
From: Ca.
Re: Emissions (Glock'94)
Which test are they going to use? The "dyno" test, or "static"? With the dyno they put it on a dyno and test the tailpipe at diff. rpms under load, then average the emission output. The static they do a tailpipe sniffer also, but it's in park and test it at idle and then again at 2000rpm. With the dyno you must have cats to pass as it also tests for Nox. If it's in good tune and you have a cat it should pass just fine. However, if they also are going to do a "visual" test, then you have to have all the original smog equipment on it. There are a lot of varying degrees of "visual". If you get someone cool-they'll let quite a few things slide just so long it passes at the tailpipe. Then there are the **** rententives.....and they'll want oe numbers for any aftermarket parts too! Just make sure you go somewhere that will "precheck " it first. If you're way over the limits you'll be labeled a "gross polluter" and have to go to a "check only" station-and they're the real buttheads!!!! Welcome to the not so wonderfull world of having to pass smog........ :cry
Pro
Joined: Jun 2001
Posts: 697
Likes: 0
From: College Station Tx
Re: Emissions (drive it)
As long as your O2 sensors are in working order and you have good catalytic converters you should be fine on the test. FWIW if you keep cats a free flow may flow 3x as much as an OEM cat's, but from the data I have seen (and experience) OEM cat's are upward of 10x as effecient at reducing emissions. If you are close to the edge and your cat's are old a set of OEM cat's might be the ticket.
You can also of course ensure your car is hot (max temp your thermostat will allow - or go to a hotter thermostat), and that you have a fresh oil change (this will actually make a difference).
With Tunercat/LT1 edit you can shoot for good l-trims (around 124) - but in closed loop there isn't much more you can do. Timing wise you can make a decent difference - but after a point you mainly end up trading off between HC's/CO2's and CO/NOx's.
Finally if you were still having problems (though you shouldn't) you can try something like a 1:6 mixture of denatured alchohol.
You can also of course ensure your car is hot (max temp your thermostat will allow - or go to a hotter thermostat), and that you have a fresh oil change (this will actually make a difference).
With Tunercat/LT1 edit you can shoot for good l-trims (around 124) - but in closed loop there isn't much more you can do. Timing wise you can make a decent difference - but after a point you mainly end up trading off between HC's/CO2's and CO/NOx's.
Finally if you were still having problems (though you shouldn't) you can try something like a 1:6 mixture of denatured alchohol.
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Emissions (drive it)
Which test are they going to use? The "dyno" test, or "static"? With the dyno they put it on a dyno and test the tailpipe at diff. rpms under load, then average the emission output. The static they do a tailpipe sniffer also, but it's in park and test it at idle and then again at 2000rpm. With the dyno you must have cats to pass as it also tests for Nox. If it's in good tune and you have a cat it should pass just fine. However, if they also are going to do a "visual" test, then you have to have all the original smog equipment on it. There are a lot of varying degrees of "visual". If you get someone cool-they'll let quite a few things slide just so long it passes at the tailpipe. Then there are the **** rententives.....and they'll want oe numbers for any aftermarket parts too! Just make sure you go somewhere that will "precheck " it first. If you're way over the limits you'll be labeled a "gross polluter" and have to go to a "check only" station-and they're the real buttheads!!!! Welcome to the not so wonderfull world of having to pass smog........ :cry
Drifting
Joined: Jul 2001
Posts: 1,418
Likes: 1
Re: Emissions (Glock'94)
How did the motor turn out? Does it run well?
If worse comes to worse you could register the car here in OK-no testing for a while but it has to be in the works.Oklahoma is a follower not a leader in that respect-the punks!
If worse comes to worse you could register the car here in OK-no testing for a while but it has to be in the works.Oklahoma is a follower not a leader in that respect-the punks!
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Emissions (mountainmotor)
How did the motor turn out? Does it run well?
If worse comes to worse you could register the car here in OK-no testing for a while but it has to be in the works.Oklahoma is a follower not a leader in that respect-the punks!
If worse comes to worse you could register the car here in OK-no testing for a while but it has to be in the works.Oklahoma is a follower not a leader in that respect-the punks!
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Le Mans Master
Joined: Oct 1999
Posts: 9,713
Likes: 3
From: Sachse Texas
Cruise-In I Veteran
Cruise-In II Veteran
Re: Emissions (Glock'94)
FWIW, I passed Dallas County emissions with a hot cam, Ed Wright tuning, 160 degree thermostat, and no EGR hardware even installed on a stock CID LT1. I don't think it will be a problem.
[Modified by Vette92, 1:10 PM 2/1/2002]
[Modified by Vette92, 1:10 PM 2/1/2002]
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Emissions (Vette92)
FWIW, I passed Dallas County emissions with a hot cam, Ed Wright tuning, 160 degree thermostat, and no EGR hardware even installed on a stock CID LT1. I don't think it will be a problem.
[Modified by Vette92, 1:10 PM 2/1/2002]
[Modified by Vette92, 1:10 PM 2/1/2002]
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 32
From: The Top of Utah
Re: Emissions (Glock'94)
Glock, you're correct. It DOES cool down the temperture of combustion. This reduces the NOX emmissions. If your test dosen't check NOX it wouldn't make any difference either way. The EGR ISN"T a power killer, becaused it is closed in the PE mode at WOT.
Drifting
Joined: Jul 1999
Posts: 1,532
Likes: 40
From: Plano TX
Re: Emissions (CFI-EFI)
I live in Collin County also and have an older (1980) vette with a ZZ4 crate motor. I think the emission numbers for the 80 are a little more lax than the newer cars so I hope I'll pass the test. Plus the ZZ4 cam has less over lap.
The only emissons item not working on the car is the EGR (air pump and converter are in place as required for original L82). The EGR is mounted on the intake, but the ZZ4 comes with the L98 aluminum heads which don't have the required exhaust crossovers to make it work.
Also, has anyone confirmed if the test will be static or dyno?
Dave
The only emissons item not working on the car is the EGR (air pump and converter are in place as required for original L82). The EGR is mounted on the intake, but the ZZ4 comes with the L98 aluminum heads which don't have the required exhaust crossovers to make it work.
Also, has anyone confirmed if the test will be static or dyno?
Dave
Le Mans Master
Joined: Jul 2001
Posts: 8,180
Likes: 2
From: Santa Maria, CA
Re: Emissions (Glock'94)
Hey Curtis. I passed my smog test this morning. After trying twice yesterday and once today. I was way over on HC's, but well within range on CO(stock O2 sensor). My 89 calls for 6* of timing. Retarded to 4*. That helped quite a bit. Then, installed "cut-back electrode" plugs gapped to .035. Poured a bottle NOSbrand octane booster since all we have is 91 octane here. Installed new O2 sensor but then the CO immediately went thru the roof. Needed to run it for a bunch a miles. Finally, it ran extremely clean and passed with flying colors. Car was down on power tho. Right after, I bumped timing back all the way up to 8*. Car screams now!
But what really helped was that the Tech and I are freinds. Follow my drift? The retarding to 4* helped me quite a bit. Also, the car did better when nice and hot!
But what really helped was that the Tech and I are freinds. Follow my drift? The retarding to 4* helped me quite a bit. Also, the car did better when nice and hot!
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Emissions (89 Paul in cal)
Thanks, I'll keep what you did in mind. I think I'll definitely have to put a can of octane booster in. I'm getting a little bit of retard right now with the 11.5:1 compression. Of course the highest in Oklahoma is 91 :mad :rolleyes: :rolleyes: :rolleyes: I think it's up to around 94 in some parts of Plano/Dallas.
Team Owner
Joined: Mar 2001
Posts: 30,828
Likes: 288
From: Boston, Dallas, Detroit, SoCal, back to Boston MA
Re: Emissions (Glock'94)
Of course the highest in Oklahoma is 91 :mad :rolleyes: :rolleyes: :rolleyes
If so Houston we've found the problem, detonation :smash:
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Emissions (BrianCunningham)
No, before it had 10.5:1 compression, and 91 octane was enough. With the 11.55:1, 91 isn't enough, I'm having to add octane booster. I was getting knock above 3k with 91 .. but i think i figured out the problem (not gas related) .. it was my Torque converter FUBARing itself.. it's making ALLL kinds of funky noise :( :cry
