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Hi all, I took my 77 for an emissions test because the libtards in charge of Colorado changed the law to basically mimic Commiefornia’s. The car failed miserably, which I thought would happen. I have adjusted the carb for maximum vacuum and have yet to take it back for the retest.
That said, is there a sensor/meter that can be used to measure AFR without putting a bung in the exhaust? I’d like to fine tune it to get as close to 14.7 as I can.
From: At my Bar drinking and wrenching in Lafayette Colorado
Vehicles built 1975+ have to pass Colorado emissions - it's been that way for many years - this is nothing new. If you live in the Metro Denver emissions area, your post-'74 vehicle has to have catalytic converters on it, and any other federally-mandated emissions equipment for the year (like an A.,I.R. pump, if required). This is nothing new - get over it.
There is no problem getting any car to pass the emission test if you have the equipment on the car. Any car can be tuned to pass the test. You don't need a bung welded into the exhaust to hook up an AFR - just stick a probe up the tail pipe and tune it. Your comments are nonsensical. Build and tune your car right, and you can have any level of power you want in a street legal car.
Can you get some time with the emissions shop to tune it? As in, they set it up, you do the work?
The issue with putting a sensor in the tailpipe is that you're getting a post-cat reading, which will be leaner than what the motor is actually seeing.
Peak vacuum is still a little on the rich side, so leaning out a bit from there should suffice.
Adding a bung to your exhaust between the engine and catalytic converter should be very straightforward for an exhaust shop to do, and it will be much easier for you to source parts that work with that. It's not difficult for me to install an AFR sensor with the car on the ground and my car is using the aftermarket 550 front springs.
what Shark Racer said is really the best way to do it but if you are dead set against welding a bung on your pipe or collector innovate motorsports makes the tailpipe adaptor for the arf sensor. part # 3728 if i'm not mistaken.
Thanks for the reply. I should add, the engine is out of a 67 Camaro and has none of the AIR equipment. Also, no catalytic converters. Unfortunately, the state of Commierado has state run emissions testing stations.
I can take a screwdriver with me and fiddle with the mixture screws after it has been tested then get back in line and repeat the process, I just don’t want to spend all day playing “will it pass or not.” I’d rather have it really dialed in and then take it in. I guess I’ll look at having a bung installed and get a handheld AFR meter.
Wow, went out and looked at CO DMV - they really are a bunch of dicks. Your best bet is to take it to a professional tuner that will show you what they are doing and why.
Yeah, for what it would cost me to return the car to the way it came out of the factory I can pay for a sh!tload of tickets for driving it without registration.
I can take a screwdriver with me and fiddle with the mixture screws after it has been tested then get back in line and repeat the process, I just don’t want to spend all day playing “will it pass or not.” I’d rather have it really dialed in and then take it in. I guess I’ll look at having a bung installed and get a handheld AFR meter.
Why would you do this? Assuming you have a good carb on there, you set the idle and cruise circuit near stoich and the power circuits/accel pump will make sure you have power when you need it.
A QuadraJet should be capable of having very good emissions in low/light throttle conditions and transition to as rich as you need under heavy or full throttle conditions. Unless you've got a cam in there that prevents you from running near stoich in these conditions, you should be able to have a tune that is good on emissions, fuel economy and performance.
Why would you do this? Assuming you have a good carb on there, you set the idle and cruise circuit near stoich and the power circuits/accel pump will make sure you have power when you need it.
A QuadraJet should be capable of having very good emissions in low/light throttle conditions and transition to as rich as you need under heavy or full throttle conditions. Unless you've got a cam in there that prevents you from running near stoich in these conditions, you should be able to have a tune that is good on emissions, fuel economy and performance.
Hi Shark, unfortunately I don’t have a Q-jet and the car is a Frankenvette. 77 body, 67 Camaro block that was built by a previous owner to be a real performer at the time. I don’t know when it was built, but my guess is late 80s or early 90s.
The enviro-***** have written the law such that a car like mine is now illegal. I’ve said for years that when they outlaw guns, internal combustion engines and any of the other pet villains of the radical left, I’d become an outlaw. So be it. I’ll continue to drive my car and pay the tickets when I get them. No big deal.
They are going to check the timing dont bother. Get the AFR a real one in there
post up your sheet this may be simpler than you thought, who knows it may run a lot better too.
Its bad out here too, 70s/80, 90s cars are having a tough time passing stock anymore....late models cant even have a tune of any type other than OEM not even a regear or they fail. A stock Fiat wont pass thier noise limits now you can get a 1000 dollar fine. Its nuts.
Greenie libtards electric only save the world types doing this. This is going to be the death of the last few American (esp Ca)aftermarket mfrs.
You didn't mention why the car failed the test. It failed an open hood inspection ? It failed a tailpipe sniff test ? Or a combination of the above or something else. If its just a Tailpipe test then getting it to a perfect 14.7 will probably fail as well with out a Catalytic converter. So what You really want is to make it so lean that it passes. Do they just test it at an Idle or did they run it at different speeds ? What happens in your state if You fail time and again. You might just be able to show receipts that You tried to make it better but can't pass.
I plan on using their own BS against them. There are times that I need Horsepower Therapy. I’m gonna call it my “emotional support Vette.” If people can have emotional support peacocks, I can have an emotional support car.
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I would lean out the carbs and set the tiiming around 5 degrees with maximum vacuum. You could always get some cheap cats and put in a test pipe section when the cats arent in there. Around here they give you a reject sticker that is supposed to give you 30 days. I saw a guy that had one that was 5 years old..LOL. I drove with one for a couple of months. no one cared.
From: At my Bar drinking and wrenching in Lafayette Colorado
Vehicles built 1975+ have to pass Colorado emissions - it's been that way for many years - this is nothing new. If you live in the Metro Denver emissions area, your post-'74 vehicle has to have catalytic converters on it, and any other federally-mandated emissions equipment for the year (like an A.,I.R. pump, if required). This is nothing new - get over it.
There is no problem getting any car to pass the emission test if you have the equipment on the car. Any car can be tuned to pass the test. You don't need a bung welded into the exhaust to hook up an AFR - just stick a probe up the tail pipe and tune it. Your comments are nonsensical. Build and tune your car right, and you can have any level of power you want in a street legal car.
Vehicles built 1975+ have to pass Colorado emissions - it's been that way for many years - this is nothing new. If you live in the Metro Denver emissions area, your post-'74 vehicle has to have catalytic converters on it, and any other federally-mandated emissions equipment for the year (like an A.,I.R. pump, if required). This is nothing new - get over it.
There is no problem getting any car to pass the emission test if you have the equipment on the car. Any car can be tuned to pass the test. You don't need a bung welded into the exhaust to hook up an AFR - just stick a probe up the tail pipe and tune it. Your comments are nonsensical. Build and tune your car right, and you can have any level of power you want in a street legal car.
Read the law, Lars. They just changed it and I’m not going to regurgitate it here for you, but it’s much more restrictive than it used to be.
Just because you’re the q-jet guru doesn’t give you license to be a dick.
they can not legally make it more restrictive than the standards were for your car when it was built in 1977. collector vehicles: House Bill 13-1071 governs vehicles that qualify to register as collector vehicles, dividing them into the following categories:
Category A includes model year 1975 and older vehicles. These vehicles aren’t required to obtain an emissions test, and owners aren’t required to sign the DR 2839 Collector’s Item Affidavit to renew.
Category B includes model year 1976 or later vehicles that were registered prior to Sept. 1, 2009. These vehicles aren’t required to obtain a passing emissions test, and owners aren’t required to sign the DR 2839 Collector’s Item Affidavit to renew. These vehicles will remain in Category B until a change of ownership occurs. The new owner may register the vehicle as a collector vehicle, but at that time it will be placed into Category C.
Category C includes collector vehicles that are at least 32 years old.
In 2015, for example, 1983 or older vehicles qualify as collector vehicles, in 2016, the model year will be 1984, in 2017 the model year will be 1985, etc.
Category C is further divided into these subcategories:
If your vehicle is registered to an address in the Emissions Testing Program Area, you must to sign the DR 2839 Collector’s Item Affidavit and pass an emissions test to register and renew.
If your vehicle is at least 32 years old and is being registered outside the Emissions Testing Program Area, you aren’t required to obtain an emissions test or sign the DR 2839 Collector’s Item Affidavit.
Lars is a very knowledgeable guy who is willing to help just about everybody. your car will fail for the missing cat and A I R setup even if it passes CO HC and NO test. it is old enough for Colorado's collector car reg which is emissions exempt. i posted the necessary paragraphs from the emissions rules they posted so you don't have to go look up the rest of the law.
This is how i passed with cat on a L-82 motor. I would wait till the last hour that the emission station was open and get the car on the highway and run it as fast as it would go to get it hot as a fire cracker. I passed every time and that cat i had was bad.
How to Measure AFR
