Emissions Testing

[Skibbe]

Car is an '87 Charger running on SMEC with a 2.5L engine.

I have to pass Illinois emissions with it...

Round 1
It's the middle of winter, so I left it alone for the first test. That means +40% injectors and a 3 bar calibration from Vellicky. I did put on a new 3" hi-flow Cat from Cat-Co, hoping that would help some. Car was at 10 psi. I failed miserably at about twice the allowed amount of everything.

Round 2
I picked up a stock 2.5L TI SMEC and swapped back to new stock TII injectors and a 2 bar MAP. I plan to head back tomorrow since it's supposed to be above freezing. Drove the car some yesterday to make sure all was well, and unscrewed the grainger. Looks like min boost is 8psi.

So, I'm really hoping I pass tomorrow since the car should basically act like stock. I could still pop the wastegate actuator and try to limit the boost more. Could also turn the fuel pressure way down but I've heard that hot and lean can cause a failure also.

Any good ideas?

[Subliminal]

They make that Guaranteed to Pass Emissions stuff. I've used it before and passed, but who knows if i would have passed anyway..?

[GLHSKEN]

Mike, drive the crap outta the car to get the cat good and hot. I passed with GLHS Stage II +40's and a 3" catco here.. but they don't check for NOX here in KY (Now they don't even have the emissions test)

[burnfaster]

Too lean & hot = failed on NOX . Retard your base timing until you get the NOX in range . +1 on getting the cat hot too . Hydrocarbons (HC) failure = too rich . A Carbon Monoxide (CO) failure is usually an ignition realted problem causing incomplete combustion of an otherwise sound mixture ie. cap , rotor , wires , coil , possibly hep .
Good Luck

[BadAssPerformance]

Limiting boost is not always the best thing on the dyno emission tests as there is a WOT portion of the test that will just run pig rich with less boost.

also, make sure your timing is 12*-14* and use stock plugs, not colder ones

also, dump in a couple bottles of HEET or ISO-HEET (better) to less than 1/2 tank of gas. the alchohol burns much cleaner than gasoline.

also, is there a stock cam in that thing? from my experience cams mess with the test results more than anything...

...the list goes on.. i should write a FAQ!

[Skibbe]

Thanks guys.

And Jason, I completely overlooked the spark plugs! Good catch... I think I have a set of 12's I can throw in by tomorrow. That may be my CO problem.

I've got an '88 TBI cam in place. If I don't pass tomorrow I still have attempt #3, so I can swap the cam, and try some Alky.

FAQ it up!

[tryingbe]

Make sure you have no vaccum leak.

[turbovanman²]

Too lean & hot = failed on NOX . Retard your base timing until you get the NOX in range . +1 on getting the cat hot too . Hydrocarbons (HC) failure = too rich . A Carbon Monoxide (CO) failure is usually an ignition realted problem causing incomplete combustion of an otherwise sound mixture ie. cap , rotor , wires , coil , possibly hep .
Good Luck

You have the CO and HC's backwards, CO is mixture, HC's is ignition, mechanical etc. :nod:

[BadAssPerformance]

HC is any wasted unburnt fuel. Could be from too rich or poor ignition or bad timing or wrong octane used or...

[turbovanman²]

HC is any wasted unburnt fuel. Could be from too rich or poor ignition or bad timing or wrong octane used or...


Yes and no, I am a certified emission technician so I know what they mean, lol. CO is fuel mixture, .5 is what we aim for for cat light off. HC's are unburnt fuel but its caused by a miss-IE bad plug, bad cylinder etc, :nod:
Octane has nothing to do with emissions unless its pinging so badly, it won't run right.

[BadAssPerformance]

I'm not certified or anything, but have experienced a couple things.

If you have 42pph injectors with a stock cal, that will raise the HC numbers. That sounds like a fuel mixture problem to me.

Lower octane fuel burns easier than higher octane fuel. I once mixed some 87 in a turbo car to pass the HC test and it did.

[turbovanman²]

I'm not certified or anything, but have experienced a couple things.

If you have 42pph injectors with a stock cal, that will raise the HC numbers. That sounds like a fuel mixture problem to me.

Lower octane fuel burns easier than higher octane fuel. I once mixed some 87 in a turbo car to pass the HC test and it did.

The HC probably came up due to rich misfire. Lets say you have .5 CO, 100 HC's and pull a plug wire on a carb'd car, the CO will basically stay the same but the HC's will jump to 2000 or so. Now do this on a fuel injected vehicle and both go up due to the computer trying to compensate.

On the other hand, if you have .5 co and 100 HC's and richen the mixture, both types, the HC's will move up a bit, usually a few hundred, so lets say 4% CO, your HC's will usually be now around 3-400.

[Skibbe]

Pulled out my test report since I have to fill out the back with the amount I spent on repairs...

HC standard is 2.00, I failed at 3.36
CO standard is 30.0, I failed at 62.6

Looks like NOx and CO2 are listed but N/A for my model year.

Does that mean I can lean the sucker out to cut HC? If their not going to look at NOx that might be an idea.

Anyway, I'm headed back this afternoon to try again with stock injectors and programming. The plugs I had on hand were actually 14s, one step hotter, so I left the 9's in there for now. I'm guessing most of my problem was the +40% and conservative (rich) tuning that Vellicky did.

My car does not like below freezing weather conditions... Wish my test month was June... I'd be more likely to work on the car outside. Oh well.

[BadAssPerformance]

I have run 1 step hotter plugs for the test before...

if no NOx test, I'd say safely lean it out a little :thumb:

Good Luck!

[turbovanman²]

Pulled out my test report since I have to fill out the back with the amount I spent on repairs...

HC standard is 2.00, I failed at 3.36
CO standard is 30.0, I failed at 62.6

Looks like NOx and CO2 are listed but N/A for my model year.

Does that mean I can lean the sucker out to cut HC?


Yep, you need to lean it out big time. If you have access to a multimeter it can help. Figure out signal wire and set scale to 1 volt DC. Road test at cruise and look at voltage, you want an average of .5 volts. If higher, then keep leaning it out until you get the average .5. Because there not testing NOX, you can lean it out further, down to .3 but don't go to far otherwise it will start to miss.

[Skibbe]

Haha... passed with flying colors this time. Car was only on the dyno for the short test.

Stock 2.5 TI cal and stock injectors:
HC .143
CO .210

Guess my Vellicky cal is pumping quite a bit of excess fuel, eh?

[GLHSKEN]

LoL...Keep that in mind and turn it down a few psi for your street driving... Better safe than sorry with a CAL