Anyone live in Portland, OR have a shop they like? Need to pass emissions…

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dkraven

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Been working on my 77 Sierra Grande for a bit now. Rebuilt the carb, threw a bunch of parts at, got the timing decent, and it’s fun to drive now. But I’m worried I won’t be able to tune it to pass DEQ. SBC 350 with a Rochester Quadrajet on it, but this model doesn’t have an EGR valve standard on it, no Cat, and it’s still a rust bucket for sure.

Anyone know a shop in the Portland area that knows carbs and can help me get the truck through DEQ?
 

Radiohead

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Can't run it through just for the readings?

I haven't had to register in the DEQ area in 20 years, so things might be different from what I remember. The dyno test was cool.
 

dkraven

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Only ever had a more modern vehicle they just plug into, so this will be a new experience for me. I know the quadrajet is a fairly emissions friendly carb, and I've read that retarding the timing and upping the idle while leaning out the air fuel screws is the way to go. That and getting it good and hot by driving for an hour beforehand. But this truck also sat in a field for 15 years and she's only got so much to give.
 

SirRobyn0

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Only ever had a more modern vehicle they just plug into, so this will be a new experience for me. I know the quadrajet is a fairly emissions friendly carb, and I've read that retarding the timing and upping the idle while leaning out the air fuel screws is the way to go. That and getting it good and hot by driving for an hour beforehand. But this truck also sat in a field for 15 years and she's only got so much to give.
My advice would be get it good and hot run it though and see what happens. If it fails at least then you know where your at. Post your failure results here. Several of us maybe able to help you clean it up if it needs to be.

Straight off the DEQ website "In the Portland Area, the vehicle testing fee is $25. This fee is due only after your vehicle receives a passing test result, and is issued a Certificate of Compliance."

So you can run it though for free if it fails, but have some knowledge at that point.
 

fast 99

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Before going in find out how they check the vehicle. When we tested here inspectors preformed an underhood check. All original emissions equipment needed to be on the vehicle and that even included the hot air tube to a stock air cleaner. There was a pamphlet with those requirements. If any parts were missing, they would not perform a tail pipe test, automatic fail.

I don't know how Oregon does their test just saying find out first. And yes, test then do any repairs if it fails.
 

Slooptin

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Not sure if this helps (I’m in Denver so we go by whatever cali does) but we have to do a 2 speed idle test for anything 1990 and older. My advice from my experience:

1. Make sure your timing is set within the factory specs (too much advance will fail)
2. Make sure it’s not too lean (will increase nox and fail you)
3. I have never had a tech pop the hood or look under the truck for cats or emissions equipment. Not saying they don’t but I’ve never had it happen to me and I know there are guys here running aftermarket carbs/intakes/headers/etc. that pass all the time. Probably not a bad idea to at least have a cat under there just in case you get a tech who really wants to be a rule stickler.
4. If you fail, it’s usually not the end of the world. I think we get 10 days to fix it and come back and retest for free so you can often make changes and show up an hour later and try again.

Good luck!
 

Catbox

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We pass in our truck usually.
Many changes have been made since it last went through.
It does need to go in for testing again as the tags are well past due.

They have not popped the hood to look under, but they do have a little mirror that they look under it with.
That checks to see if you have cats if your truck required them.
Ours does, so we have empty cats under the truck currently, for compliance.
It passes emissions just fine like that.
Just some tuning to be done...
 

DoubleDingo

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Adjust it like others have stated, get it hot, and get it tested, you'll be fine
 

DoubleDingo

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You have the no egr and no cat on your side. That alone makes it much easier to pass, and it being a 3/4 ton is a plus because the requirements are more lax. One reason I won't alter my c20 nor sell it. The guy that runs the smog shop I go to, tells me each time I take the c20 in there, "Don't sell it". I've only had one fail and it was dumping too much fuel. Retested with a rebuilt national carb, and it passed. I bought the rebuilt carb because I needed the truck to run so I could get the tags, code enforcement was breathing down my neck and the truck was closest to the road, so if they wanted to be pricks, they could have easily towed it off even though it's parked on my property.
 

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