I need to get my car though emissions by the end of the month. Last time it maxed out hydrocarbons on idle but was very clean everywhere else, both at idle and the dyno.

I just picked up a new timing light with a dial for advance. My timing right now is 20*(i was guessing 13-14) at idle(750rpm) and 34 degrees total (no vacuum). Obviously its a crappy curve. The car has a nice lope and plenty of power this way.

I need to get the hydro down from 1320 to 120. So my plan is to drop the timing down to 8 or lower?, and raise the idle to 1000, then adjust the mixture for the highest vacuum. Sound like a good start?

btw its a non cc qjet
214/224 cam

 

uh, retarding the timing raises the HC and CO, lowers the NOX, if you NOX is good, or better yet not tested (not tested in all states, I'm not sure about BC.) you want to advance you timing as far as you can without it pinging, also you can lean the mixture out, also be careful with pinging. If you HC is high, that you gas isen't being burned completely, and if your CO isen't also high it's running rich, and it needs to be leaned out, if CO is also high than than the mixture is close to correct than advanceing it will increase your combuston temp and ithe fuel will be more completly burned, but if they test for NOX (oxides of nitrogen) it will through that off, because NOX forms at high combuston temps. just my $0.02

 

See thats what i thought at first, it seems perfectly logical the way you describe it, but i've read many posts about people needed to retard the timing to pass emissions. Maybe i missed something.

The first time i took it through i had the timing at 10 and the carb wasnt tuned. Since i've set the timing to 20 and tuned the idle mixture, but havent retested yet.

I do get pinging in the 4500-5000 range with 87 as it is now.

[edit]
so i did a search on hydrocarbons and nearly every piece of advice was to pull timing. So what should i do to clean it up? Increase the idle?

 

I don't believe that dropping the timing to 8 degrees will help all that much. I run 14 degrees lead with vaccuum advance ( 15 degrees ) hooked up to full manifold vaccuum.

I live in Coquitlam so I have to pass Aircare as well. My car (350 ci )has 10.3 to 1 CR and a 218\228 cam 112 LCA. Much modified Holley 780VS ( Weber Powerplate and Annular boosters ), although a Qjet should be able to run at least as clean.

HC at idle is 44, CO is 0.00. HC driving is 6.00 and CO is again 0.00. NOx is 370.00 .

Couple of things. High HC at idle usually means it is too lean ( Co usually quite high or close to limit ). Check for vacuum leaks or mixture being set too lean ( yes ...too lean ) at idle.

Switch to Mohawk 94+ gas...it really does make quite a difference. 10% Ethanol content in the 94+.....none in 87 octane.

How old is the catalytic convertor? A new cat works wonders!! An old cat is least effective at idle....so that could very well be your problem. Lordco sells universal cats. You might want to make up a test pipe with bolt on flanges. A.... ummm....friend of mine, only uses his cat once a year...guess when

If you want to stop guessing aboout your idle setting , go out and buy a K&N Air\Fuel monitor. Set idle at between 16 to 14.7 to 1.

Lastly...why do you have to get HC readings down to 120? I have a 1986 Camaro that originally had an LG4. HC limits are 339 ppm. Make sure that they have your car tested by the serial number with a listed engine size of 5.0L. Do NOT tell them that you have a 350!! They don't open the hood. If you tell them you have a 350 then the dummies punch that into the computer and you get the emission limits for a 350......which was only available FUEL INJECTED , and the limits are much lower than the carburated cars. BTW...Mapleridge seems to be the testing station of choice.

Hope this helps.

PS...what the heck are you running 87 Octane in a HO motor?? No wonder you get pinging on the highway. Yeah...I know gas prices are high, but you should be running at least 92 ( or higher ) in that motor....with that much timing. Run Mohawk gas only, Chevron as second choice. Stay away from Shell and PetroCanada...goat ****.

 

this is from my collage book that I dusted off- Automotive Technology, a ststems approach, 2nd edition, 2nd revision Ch 26-Emission Control Systems, pg 685

Excessive HC emissions may be caused by:

ignition system misfiring
Improper ignition timing (retarted)
excessively rich air/fuel ratio
low cylinder compression
defective valves, guides, or lifters
vacuum leaks

Excessive CO emissions may be caused by:

rich air/fuel mixture
dirty air filter
faulty injectors
higher-than-normal fuel pressures
defective system input sensor

Excessive HC and CO emissions may be caused by:

plugged PCV system
excessively rich air/fuel ratio
stuck open heat riser valve
AIR pump inoperative or disconnected
engine oil diluted with gasoline

Lower-than-normal O2 readings may be caused by:

rich air/fuel mixture
dirty air filter
faulty injectors
higher-than-normal fuel pressures
Restricted PCV system
charcoal canister purging at idle and low speeds

Lower-than-normal CO2 readings may be caused by:

leaking exhaust system
rich air/fuel mixture

Higher-than-normal O2 readings may be caused by:
an engine misfire
lean air/fuel mixture
vacuum leaks
lower-than-specified fuel pressures
defective fuel injectors
defective system input sensor


this is directly from the book take it for what it's worth, I wonder why NOx isen't on this table

 

lots of points to address
-i ran 94 mohawk at the test, the engine had 50 km's on it, everything was new
-i dont know why the limit is 123 thats what it is for 85, they think its a 5 litre i didnt say anything
-i use 87 because it only pings on hot days at very high rpms, which im not usually at, its a daily driver
-idle co was low, about 0.27
-everything on the engine is new, it has 3000 km's now, no vacuum leaks solid 15" inches at idle
-i have intalled an o2 sensor recently but havent had time to hook it to my volt meter

i'll fiddle with it when i get some free time

 

Key question is...how old is the cat?

FYI:

Somethings wrong with the specs that you were given. I just went to the Aircare site and punched in a 1985 Camaro. Here are the results:

Driving Mode HC Standard: 207 parts per million
Driving Mode CO Standard: 1.42 percent
Driving Mode NOx Standard: 2081 parts per million
Idle Mode HC Standard: 344 parts per million
Idle Mode CO Standard: 3.97 percent


http://www.aircare.ca/inspinfo-stds-...5.0&W=1320&G=0

Edit: Note that they have a list of all specifications for all Vehicles available for download in PDF form. I'd print out the online specs for your vehicle and take a printed copy of the specs down to the testing station and show it to them. Something is entered wrong on thier end. Print out the PDF table as well.

BTW....Yes I've had lots and lots of experinece getting my car through AirCare. Had some tricks for the carb when it also had the Q-jet off the 305 and switched the engine to a 350. Let me know if you still have problems once you set things up with the O2 sensor.

PS: here's the site to punch in your vehicles info:

http://www.aircare.ca/inspinfo-standards.php

 

Your links inspired me to find out how they do things here in Colorado.

The curb weight isn't factored - Colorado just has different standards for GVWR less than 6000 lbs (passenger cars, etc.), 6000 to 8500 lbs, and over 8500 lbs.

There are no distinctions made between idle and "driving mode" emissions.

I pulled out my 2001 and 2003 inspection reports for the Camaro and compared them to the (newly-found) standards on the Colorado website. I now am okay with the fact that my readout always says "1982 2.8l 6 cyl", since all they've done to date is scan the VIN and ignore the under-hood stickers (which match the engine). Why? Because the 1982 standards are looser than the 1986 standards, and I would have failed in 2001 for CO (but it was cleaner in 2003 after the mods, and would have passed the 1986 standards - it even meets the 2003 model year standards, for that matter, but not 2006).

FWIW, the report pre-print has this information:

High HC - unburned or partially burned fuel.
High CO - air/fuel mixture too rich
High NOx - high combustion temps and/or high combustion pressures.

A high overlap cam will cause idle HC problems. So will leaky exhaust valves or weak firing plug. Or a shot cat. Or no A.I.R. system.

 

ah you know what it was my girl friends car i was thinking about for the 123. I just had to get her car through recently and it was failing idle hc. a 90 240xs.

I dont know how old the cat it, but its not original, its not that rusty. I have the aircare history for the car from the website and it failed really bad in 99 (i just bought it this year) was re tested later that year and passed no problem. So im guessing thats when the cat was replaced.

Car has no air system, no egr, everything was missing when i bought it except the cat. First thing i did when i put the new engine in was check to make sure it wasnt hollow. I had a vette that wouldnt pass air car no matter what i did, turned out the cat was gutted.

 

Finally got it through

Turns out dropping the timing to 8 (against everyones advice here) got it through. It sounds like its going to die and its running like crap but it passed.

I wish i had tried my original plan before i spent 100 dollars failing 4 tests.

 

Hey I just got a 92 camaro rs with a 350 swapped in it. I'm scared that it won't pass emission testing. I'm from ct. If anyone could tell me what I should do please help ha.

 

Was it a god swap? By this I mean did they keep all the emissions gear on it. Or did they put a carbed 350 in it? If you test & fail, its not the end of the world, they give you time to get it fixed.

 

Dude, you bumped a 7 year old thread. Your other 2 reposts were bumping other old threads with the same questions.

Why not post a new thread of your own and give all of us details on your car that would help us help you?