Yet another LS Swap - CO

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You don't need to use the stock manifolds, just have the cats and sensors the same distance away as if they were stock. The path can be different, the distance can't. After the cats, you can do as you please.

It seems you were hoping they would hold you to '02 avalanche standards, even though avalanches never came with LS1's? I know a lot of people say they're doing an LS swap, yet they put a vortec in. But, avalanches, to my knowledge, never came with a 6.0 motor. Just LM7 and that 8 something liter beast.

As I was told you can't swap out anything on the exhaust from the CATs forward. CATS back you can change whatever you want. But Manifolds, O2 and CATS have to be stock. That is what the guy at the emissions place told me. I think this especially holds true if you have a EGR as part of the system.
 
You don't need to use the stock manifolds, just have the cats and sensors the same distance away as if they were stock. The path can be different, the distance can't. After the cats, you can do as you please.

It seems you were hoping they would hold you to '02 avalanche standards, even though avalanches never came with LS1's? I know a lot of people say they're doing an LS swap, yet they put a vortec in. But, avalanches, to my knowledge, never came with a 6.0 motor. Just LM7 and that 8 something liter beast.

Also I mis-spoke, I have my buddies avalanche on the brain. My motor is technically a LQ4, we "based" most everything off 2002 Silverado
 
just curious, what if you get the swap done and then pass the rapid screen? Just a thought for those who are already registered....
 
How does TLC 4x4 in Ca get around this. They have done a ton of V8 swaps in various Land Cruisers.. If Co is following Ca standards it might be worth a call to Jonathan Ward and ask.
 
How does TLC 4x4 in Ca get around this. They have done a ton of V8 swaps in various Land Cruisers.. If Co is following Ca standards it might be worth a call to Jonathan Ward and ask.

Pretty sure they use the GM E-Rod packages, which are 50 state legal create engine systems engine, ecu, cat forward exhaust. All in one purchase.
 
As I was told you can't swap out anything on the exhaust from the CATs forward. CATS back you can change whatever you want. But Manifolds, O2 and CATS have to be stock. That is what the guy at the emissions place told me. I think this especially holds true if you have a EGR as part of the system.

If that's the case, then I'm fawked. Currently tearing down my truck for a turbo build. Have you *tried* another emissions location? That would be my first step. I really have trouble believing they so fundamentally changed the rules without any public notification. As I posted earlier, I have a lot of experience wrestling with Clean Air Colorado and there are ways around a failed emissions test, but seriously, I think this guy is yanking your chain or has not been properly trained (who at CAC has?)

:edit: for the record, my friend just recently registered a tube-frame race car that was built 100% from scratch in his own garage. Honda motor with a turbo, single cat and motorcycle style muffler, basically nothing was factory but the engine block (internals were changed). They didn't give him any trouble except for the stolen transmission, lol. This was like 6 months ago.

Luke111 said:
How does TLC 4x4 in Ca get around this. They have done a ton of V8 swaps in various Land Cruisers.. If Co is following Ca standards it might be worth a call to Jonathan Ward and ask.
If CO is following CA standards, I'm taking my job, my family and my tax revenue to Wyoming.
 
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Wow, sorry to hear the news. I've yet to do a swap for CA or CO and the more I hear the less likely I ever will. It's just another case of too much government intrusion in our lives. I think there should simply be a sniffer test, pass or fail, done. Georg at Valley Hybrid once told me a story of a fail in CA because a cat was a couple inches out of place.

I would look for a work around. I know that here in SC there is no inspection and in SC if a vehicle spends 183 days or more here it can be registered here. So people in NC, where there is inspection, write a storage contract with someone in SC for said vehicle
 
As I posted earlier, I have a lot of experience wrestling with Clean Air Colorado and there are ways around a failed emissions test, but seriously, I think this guy is yanking your chain or has not been properly trained (who at CAC has?)

If you read up on the interwebz or give them a call, the "inspectors" (aka "referee") are very knowledgeable. Granted, I haven't been to be inspected yet, but I have talked to them on the phone. I think for the case of the OP, there are things they'll let slip by (like walker cats for OE cats, non-stock exhaust manifolds if you mimic as closely as possible and still place cats the same distance from the manifolds), but when you go in with some big no-nos, as the OP did, they throw the book at you. It's not impossible nor does it seem to be a guessing game where no one knows the rules.

The OP would have to change his motor back to a stock configuration, get ALL his O2 sensors and Cats in the correct spot and I bet he could pass if everything was up to snuff. In fact, selling the "upgraded" LQ4 or piecing it out then dropping in a new LM7/LQ4 would probably be the cheapest way out of this if they wanted to be legal in Colorado. The wiring is already done, hoses are made up etc.
 
If that's the case, then I'm fawked. Currently tearing down my truck for a turbo build. Have you *tried* another emissions location? That would be my first step. I really have trouble believing they so fundamentally changed the rules without any public notification. As I posted earlier, I have a lot of experience wrestling with Clean Air Colorado and there are ways around a failed emissions test, but seriously, I think this guy is yanking your chain or has not been properly trained (who at CAC has?)

:edit: for the record, my friend just recently registered a tube-frame race car that was built 100% from scratch in his own garage. Honda motor with a turbo, single cat and motorcycle style muffler, basically nothing was factory but the engine block (internals were changed). They didn't give him any trouble except for the stolen transmission, lol. This was like 6 months ago.

If CO is following CA standards, I'm taking my job, my family and my tax revenue to Wyoming.

You'd have to provide more details about that tube buggy to be relevant.

Year? What was the original VIN? What county? Registered with insurance and license plate for unrestricted road use?
 
If that's the case, then I'm fawked. Currently tearing down my truck for a turbo build. Have you *tried* another emissions location? That would be my first step. I really have trouble believing they so fundamentally changed the rules without any public notification. As I posted earlier, I have a lot of experience wrestling with Clean Air Colorado and there are ways around a failed emissions test, but seriously, I think this guy is yanking your chain or has not been properly trained (who at CAC has?)

:edit: for the record, my friend just recently registered a tube-frame race car that was built 100% from scratch in his own garage. Honda motor with a turbo, single cat and motorcycle style muffler, basically nothing was factory but the engine block (internals were changed). They didn't give him any trouble except for the stolen transmission, lol. This was like 6 months ago.

If CO is following CA standards, I'm taking my job, my family and my tax revenue to Wyoming.

You might not be hit the same issue I did. So, when you roll into a Colorado emissions station, one of the first things they do is open the Driver's side door and look for the bar code. They scan that, and that set's their computers to make, model, engine of what that bar code says your vehicle has. Then they pop the hood, they do a visual, there is usually a sticker on your hood that shows where the ERG, EVAP, and any other emissions controls systems are. The make sure they are there and then they plug into your ODB port. Their computer will pull codes, check your computer, make sure all the DTS sensors are working etc.

So in my case when I rolled in, they opened the hood and found that my engine didn't match the picture on the hood, and when they scanned my barcode and the computer was setup for a Toyota, but when the plugged into mine it came up as GM, that is what sparked the full on inspection.

And I am sorry... I guess I wasn't all that clear, if you have to go through a inspection that is where they are now holding us to CA/Federal emissions. For me, in the eyes of the emissions gods everything about my setup is evil. Again modifed motor, modified computer, modified exhaust (headers and my drivers side CAT was 4 inches too far back), etc, etc.

Also I decided to go big. I went with the 6.0L (LQ4) which was most commonly only in heavy duty trucks. They had it is some others, but my computer says 2002 Chevy Silverado HD. So they flagged me on having a heavy duty engine in a light duty truck.

Looking back on this, had I had to do it all over again, I would have just got a 5.3L and kept everything stock and I wouldn't have the issues that I am having. So I do think it is possible to keep doing cool things with cars in Colorado, I am just more aware that if having to go through a inspection process (which isn't common) that things need to be factory.
 
So, did you actually go to a referee or did you go to an inspection station where they do emissions only?

BTW, the lq4 is denali's, escalades etc as well.
 
You'd have to provide more details about that tube buggy to be relevant.

Year? What was the original VIN? What county? Registered with insurance and license plate for unrestricted road use?

No original VIN, was built completely from scratch with no donor frame, etc. An original VIN was assigned by state patrol after they inspected it (and confiscated his stolen transmission). Denver county. It has insurance and a license plate just like my DD.
 
So, did you actually go to a referee or did you go to an inspection station where they do emissions only?

BTW, the lq4 is denali's, escalades etc as well.

I had a appointment setup with a inspection people "referee". I did goto the normal emissions place first, and that wasn't the issue, but they gave me the forms and contact numbers for the full on inspection places. I had to setup a appointment for them to go through the truck which is where I got the full write up.
 
And I am sorry... I guess I wasn't all that clear, if you have to go through a inspection that is where they are now holding us to CA/Federal emissions. For me, in the eyes of the emissions gods everything about my setup is evil. Again modifed motor, modified computer, modified exhaust (headers and my drivers side CAT was 4 inches too far back), etc, etc.

Also I decided to go big. I went with the 6.0L (LQ4) which was most commonly only in heavy duty trucks. They had it is some others, but my computer says 2002 Chevy Silverado HD. So they flagged me on having a heavy duty engine in a light duty truck.

Looking back on this, had I had to do it all over again, I would have just got a 5.3L and kept everything stock and I wouldn't have the issues that I am having. So I do think it is possible to keep doing cool things with cars in Colorado, I am just more aware that if having to go through a inspection process (which isn't common) that things need to be factory.

OK, after reading this explanation, sounds like your problem could be solved by just swapping out the computer? I'm pretty sure the 6.0 came in some 1500s and tahoe/suburban/escalades too. Would that not make everything jive from their perspective?

I have registered a V8 swapped cruiser from out of state, which is the same inspection process as performing your own swap, as far as I know. They plugged in the scanner, checked for EGR, PCV and cat (that's all the emissions equipment my donor year TBI came with) and printed me up a nice piece of paper. FWIW, location of cats and o2 sensors was a non-issue, as long as they're there.
 
OK, after reading this explanation, sounds like your problem could be solved by just swapping out the computer? I'm pretty sure the 6.0 came in some 1500s and tahoe/suburban/escalades too. Would that not make everything jive from their perspective?

I have registered a V8 swapped cruiser from out of state, which is the same inspection process as performing your own swap, as far as I know. They plugged in the scanner, checked for EGR, PCV and cat (that's all the emissions equipment my donor year TBI came with) and printed me up a nice piece of paper. FWIW, location of cats and o2 sensors was a non-issue, as long as they're there.


It's a bit more then just swapping out the computer for me. The list I made for making this legal to go through emissions again would be :

I have to swap out to a computer / system that is light duty. I was looking at the Denali setups. If I based off the Denali I will have to add/do :

EGR - Will have to add this back, and get the right Denali intake that has the EGR provision (my inake doesn't have the EGR hole.)
EVAP - Have to source a Denali evap canister
Wiring - My harness was based off a 2002 HD Silverado, so it doesn't have the wiring for the EGR or EVAP so I will have to add the right sensors back in...
Re-work drivers side exhaust to move cat forward
Factory computer for a Denali
Get a set of Denali injectors (maybe)

This was my high level list
 
OK, that list sounds pretty manageable to me. If I were you, I'd change out the computer, wiring, intake/EGR & charcoal can then take it to a different inspector. I'm guessing if the equipment is there and matches what their OBD scanner says, they will overlook the location of cats, etc.

I guess what I'm trying to say is DON'T GIVE UP ON THE TRUCK! Compared to the work you've already done, the remaining stuff to get this thing to pass emissions is small potatoes.
 
It's a bit more then just swapping out the computer for me. The list I made for making this legal to go through emissions again would be :

I have to swap out to a computer / system that is light duty. I was looking at the Denali setups. If I based off the Denali I will have to add/do :

EGR - Will have to add this back, and get the right Denali intake that has the EGR provision (my inake doesn't have the EGR hole.)
EVAP - Have to source a Denali evap canister
Wiring - My harness was based off a 2002 HD Silverado, so it doesn't have the wiring for the EGR or EVAP so I will have to add the right sensors back in...
Re-work drivers side exhaust to move cat forward
Factory computer for a Denali
Get a set of Denali injectors (maybe)

This was my high level list

The castings as well, so you probably need new heads? I don't know how they found out about the cam, but I assume you can sweep that under the rug somehow?

My guess is, you could get the current computer through, if all DTC shows, computer is locked and the tune is "factory." You're just horse trading if you get your PCM programmed with an escalade VIN, which in 2002 didn't have EGR I believe.

Personally, I'd fix all the musts for an '02 silverado and try it that way. If they have heart burn over the 2002 silverado, I'd tell them you'll trade for an escalade motor and it will be the same thing. If that didn't work, I'd go back a month later with a reprogrammed PCM and 2002 escalade vin.
 
Scottyrana had a great solution. Do the LLC thing in Montana and keep your amazing cruiser. Even though I am sure many on here, including me would like to buy it.
 

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