Smogging a custom tune, etc.
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From: Central Cal.
Smogging a custom tune, etc. A hypothetical situation, if you will. A mostly stock LC9 5.3 going in an '86 El Camino. The non-stock parts are the OEM heads getting ported(should not be an issue), and a cam with 210/216 duration, .553/.553 lift, 115 LSA. This cam should idle like a stocker. So no red flags so far. But it WILL need a custom tune to run right, right? And there's the rub. From what I have read here, any non-factory tune molesting DOES throw a red flag via the OBDII port. So the question is, is the above setup possible in the glorious state of California?
I know guys have passed with the hi-lift Hot cam from WS6store. So how did they do it? They must have needed a custom tune.
I know guys have passed with the hi-lift Hot cam from WS6store. So how did they do it? They must have needed a custom tune.
Last edited by G Atsma; Jan 28, 2018 at 08:54 PM.
I dont see a tune messing with smog testing. As long as its tuned right it shouldnt be an issue. Dont see it being any different. No codes, good afr, no evap crap, etc. Shoulf pass without a problem.
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I thought there had to be a "tag" of some sort to show the tune was a factory flash. I hope you're right. I would keep all emissions gear on it(not that there is much beside evap and converters). Thank you for responding!
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You are fortunate! But I guess there is a price for the now non-smoggy air around the LA basin. And I do think one can have a smog-legal performance vehicle that can be fun to drive. Just takes a little more doing..
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They would need the Calibration Verification Numbers to know the calibration has been altered, That's how GM techs/dealers know the tune has been altered for warranty denial purposes.
Of coarse....They would need know if the CVN's are from GM or not, I highly doubt GM is required to surrender such info, Besides it would have to be updated almost daily.
Doesn't Cali put cars on rollers & measure emissions output?
Of coarse....They would need know if the CVN's are from GM or not, I highly doubt GM is required to surrender such info, Besides it would have to be updated almost daily.
Doesn't Cali put cars on rollers & measure emissions output?
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I am in AL so i have similar luxuries as brandon. However i thought they based the emissions from the vehicle, where a 86 elco with a modern v8, converters and evap should pass with flying colors. Has this changed now where they base it off the engine? What if it was a carbed 350 in the same car, which is about what an 86 couldve been equipped with?
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From: Central Cal.
Clinebarger and Lsxford, both of you make good points! I have to look into how it is done as per year of engine vs. year of vehicle. '96 and newer are tested by merely plugging into the OBDII port and looking to see if the converters are in place. I was figuring on wiring in an OBDII port for whatever reasons come up. Thanks, both of you!
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From: Fort Worth, Texas
That's how they do it in "Emissions" Counties in Texas. They just look to see that all the "Readiness Monitors" are "Ready" & that's there are not any DTC's present.
They are suppose to visually check for catalytic converters, But they don't.
They are suppose to visually check for catalytic converters, But they don't.
california, yikes. i know a little from a buddy who just moved down there (with a 5.3 swapped elky, lol)
so the vin in the ecm cant be from a truck or suv. you'll have to use a car vin for the swap.
or, you can find someone to clone you an erod pcm that would pass.
other than that...register it at "grandpa's house" up in humboldt or one of the other no smog counties
so the vin in the ecm cant be from a truck or suv. you'll have to use a car vin for the swap.
or, you can find someone to clone you an erod pcm that would pass.
other than that...register it at "grandpa's house" up in humboldt or one of the other no smog counties
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From: Turnin' Wrenches Infractions: 005
They would need the Calibration Verification Numbers to know the calibration has been altered, That's how GM techs/dealers know the tune has been altered for warranty denial purposes.
Of coarse....They would need know if the CVN's are from GM or not, I highly doubt GM is required to surrender such info, Besides it would have to be updated almost daily.
Doesn't Cali put cars on rollers & measure emissions output?
Of coarse....They would need know if the CVN's are from GM or not, I highly doubt GM is required to surrender such info, Besides it would have to be updated almost daily.
Doesn't Cali put cars on rollers & measure emissions output?
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From: So.Cal.
In CA:
vehicle after 2006: BAR/CARB database contains vehicle's VIN, calibration id, and CVN; this is the baseline, and any tuning is detectable.
vehicle prior to 2006: BAR/CARB database does not know the calibration id/CVN that the vehicle came with; i.e. their database has no baseline.
what I'm not sure about is this: with a 2006-or-earlier vehicle, when you show up for smogging at some point in time, do/did they store the calibration id and/or the CVN (which now becomes the baseline)...?
if they don't store the calibration id/CVN, then they won't be able to detect that the tune has changed.
Also, it seems they now check the readiness monitors in 2 steps:
a. they see what monitors are ready or not ready;
b. near the end of the test, they reset the monitors, they then check that NONE are ready;
so step b. weeds out any emissions defeat done to the tune.
vehicle after 2006: BAR/CARB database contains vehicle's VIN, calibration id, and CVN; this is the baseline, and any tuning is detectable.
vehicle prior to 2006: BAR/CARB database does not know the calibration id/CVN that the vehicle came with; i.e. their database has no baseline.
what I'm not sure about is this: with a 2006-or-earlier vehicle, when you show up for smogging at some point in time, do/did they store the calibration id and/or the CVN (which now becomes the baseline)...?
if they don't store the calibration id/CVN, then they won't be able to detect that the tune has changed.
Also, it seems they now check the readiness monitors in 2 steps:
a. they see what monitors are ready or not ready;
b. near the end of the test, they reset the monitors, they then check that NONE are ready;
so step b. weeds out any emissions defeat done to the tune.
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From: Central Cal.
Thank you joecar! What about a tune where all emission gear is intact, but some retuning has taken place to accommodate a VERY mild cam and CNC'd heads. Still a very smooth idle. Would that vehicle fail? An OBD2 plug would be available, but it would be a swapped vehicle, maybe '80's vintage.
Wondering if your bigger challenge might be the visual inspection. Thinking 86 model year gets tailpipe sniffer and open hood rather than plug in for readiness, which is OBDI in your case ? If you can find the proverbial "friendly" smog shop that knows ls architecture from sbc and will ignore the obvious difference as long as hydrocarbon counts,etc are good and cats in place? In AZ if you engine swap and vehicle is less than 25 years you need to meet standards for year of engine manufacture. Guessing CARB declares swaps verbotten, period.
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From: So.Cal.
Thank you joecar! What about a tune where all emission gear is intact, but some retuning has taken place to accommodate a VERY mild cam and CNC'd heads. Still a very smooth idle. Would that vehicle fail? An OBD2 plug would be available, but it would be a swapped vehicle, maybe '80's vintage.
my understanding is this (regarding earlier-than-2006 vehicles):
- if they do not store the CVN then they won't be able to detect any tuning.
- otherwise if they store the CVN, then they can compare the current CVN to any previous CVN they have on your vehicle (they may have been saving these since 2012, I'm not sure about this, I'm trying to find out more), so this might raise some questions (I haven't been game enough to try this yet).
Interesting, thought I'd heard that CARB wasn't allowing any changes without their certification. Have seen some posts here about getting pulled over and receiving a referral to a state referee for non conforming equipment but sounds like you have that covered. That's a pretty mild cam btw so should pass. Those specs make me think it might be an Elgin.
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Usually if there's something that isn't defined "in the book" so to speak, then you get referred to a referee to look it over and see if in fact all is hooked up and blowing clean exhaust. At least that's the way I understand it.