Passing CA Smog help - High HCs

DoubleDingo said:

Timing is not set by what CA wants, you set it to what the engine likes, same with the carburetor, and you use a vacuum gauge and timing light for best results. Correct plugs and proper plug gap is critical as well. You still need to answer some questions and post some pics of the engine. We are trying to help you out, but without information or photos of what we are trying to help with, all of us are just throwing darts in the dark. Can't hit the bullseye when you can't see the danged dartboard.

Click to expand...

DD
He's trying to pass CA smog. If its not set at the setting on the smog label (or whatever the spec is for that year) he will get dinged and/or fail. On carbureted vehicles they used to put a timing light on and check it, been 20+ years but I would assume they still do.
Butch

77Matt said:

No, it runs like crap. I tried adjusting and had some other shade tree mechs look at it. The EB was way better but CA says nope. This one is beyond my capabilities and I am planning on taking it to a QJ specialist. I might just let CA win this one, sell it and buy an exempt truck

Click to expand...

Matt
Don't give in to the b@$t@rd$. If you have a knowledgeable q-jet person available I would recommend using them. Q-jets came on 305-454, cars, trucks and land yachts. if you got one from the wrong engine size it could have wrong jets, primary metering rods, secondary metering rods or hangers. Way too many combinations available. If it is the factory carb that should not be an issue.
May be a silly question, but have you verified that the choke is fully open when the engine is warm?
Butch

I wonder if a cat converter is N/A for this model year and "heavy duty" would putting any cat converter in fail the test?

Because this sounds like a simplest solution to get the HC down.

I'm running high flow Magnaflow cats in all my past and present Japanese cars to get rid of the smell and headaches in traffic jams. It is also enough to pass Polish inspection for my Euro III WRX provided that I come fully warmed up and hold the RPMs long enough during sniffer check.

77Matt said:

It ran fine on the EB so I don’t think it’s spark or fuel. Timing was offset to the max allowable by ca. There is a ton of exhaust so I thought it was running super rich and couldn’t dial it back. I figured the hinge pin was stuck and not dropping in. When I opened it up it was th opposite, the hinge pin didn’t have the little hook to hang on the float. So after fixing that and adjusting the float, I was back at square one. The vacuum set up is slightly different between the 2 carbs so that could be a clue. The new carb does not have one of the ports the old carb had. There’s a port that goes from the carb body to a control valve and then back to a 2nd vacuum break. I tested for the correct vacuum type and Td off another and seems to be correct. Basically with the new carb, there’s a ton of exhaust and it runs louder and rougher. I can send some pics later. Thanks!

Click to expand...

The fact that you had to open up the carb and make repairs on a "fresh" carb concerns me. I'd definitely reach out to National to get their 2cents. If those basic items were wrong, then I'd question the whole thing. If you wanted to check, you could verify the idle mixture screws. You could turn them in and count the number of turns. They should both be the same # of turns between the left and right side and likely between 2-3 turns.
I'm not sure what you mean by "ton of exhaust". Is that black smoke out of the exhaust or a rich smell? Also, I'm not sure what louder would be, but rougher does sound like it could be way out of tune or the carb is just dumping fuel. I'd pull a couple of plugs to verify.
For the vacuum, I'd start off by plugging all of the vacuum ports on the carb to remove any variables. Note, if you were running off manifold vacuum with the Edelbrock, you will likely need to adjust the timing since you'll be running port vacuum with the Qjet.
Reminder, port vacuum = no vacuum at idle. Manifold vacuum = vacuum all the time. It should run just fine with all ports on the carb plugged, at least for this debugging.

ButchM said:

DD
He's trying to pass CA smog. If its not set at the setting on the smog label (or whatever the spec is for that year) he will get dinged and/or fail. On carbureted vehicles they used to put a timing light on and check it, been 20+ years but I would assume they still do.
Butch

Click to expand...

Mine is set to 10btdc, not 4 like the label says. The engine is tuned correctly as well as the carb, and as you can see it passes with flying colors. I posted my recent results somewhere in this thread.

@mibars Instant fail if you add a catalytic converter to a vehicle that didn't come with one. We covered this earlier in the thread.

I am out. He doesn't seem to care enough to get the help we are trying to provide.

On the contrary I am taking all the advice I can get. But as I work and have children, I cannot respond as quickly as some would like. I also have limited experience with some of the things asking. I can tell you yes it is running rich, just dumping fuel even after adjusting the float. Timing was previously set by a smog referee to max off center and ran fine on the other carbs including 1 qjet. From what I was told, swapping carbs shouldn’t require timing. I can’t remember the plug spacing off hand but I can tell you that it is correct to the specs of the truck. I could not find a vacuum leak but I will try a different set up. My neighbor is a seasoned mechanic basically said I need a specialist after looking over it and recommended somebody.

DoubleDingo said:

@mibars Instant fail if you add a catalytic converter to a vehicle that didn't come with one. We covered this earlier in the thread.

Click to expand...

LOL, it's ridiculous, making the vehicle cleaner than it should be fails the "clean" check. But law is law heh...

Just a quick update- I talked to the ‘specialist’ and gave him the rundown. The short answer was get a different smog guy. He said cap the ‘egr’ port because it isn’t required. I need manifold vacuum for the ported vacuum switch so my plan is to tee off from the brake booster. So short answer is that the set up I had is basically up to the discretion of the inspector. In other words, if a port on the 1400 says ‘egr’ port and is capped, an inspector may flag that as modified. Even though the specialist is a pro quadrjet, he says the quick fix is get a different smog guy lol. I am going to put the EB back on and see what the emissions are.

Success! Edelbrock 1400 was the answer. She's CA SMOG legal!