I took my 69 Z thru inspection today and everything was good except the emissions. I really could use some expert help if any can be had. To start, the engine is completely stock. 30-30 cam, 4053 carb, intake, exhaust and so on. The first pass thru the HC (PPM) was 2113 (900 limit), CO (%) was 2.67 (9.00 limit) this passed, and the CO (%) + CO2 (%) was 9.58. The second pass the result was a "BYPASS"?, whatever that means. I really don't know what I need to ask here to fix this, but I sure could use some help now if I ever needed it. I live in Delaware and yes they still sniff cars as old as my 69. It just plain sucks. But I can't do anything about that. I had a local shop "TRY" to take care of this today. $100.00 out the window.

:mad:

That's ridiculous that they pick on these old cars like that. Sorry to hear about your issues. I'm sure someone here will be able to provide some good ideas to help, unfortunately I know very little about emissions.

Is that your everyday ride? If it isn't, here in NJ you could get historic plates and thus no inspections of any type.

This might sound dumb, but I see emission related threads at http://thirdgen.org/techbb2/ all the time. I guess because those newer cars are never exempt.

Is that your everyday ride? If it isn't, here in NJ you could get historic plates and thus no inspections of any type.

This might sound dumb, but I see emission related threads at http://thirdgen.org/techbb2/ all the time. I guess because those newer cars are never exempt.


Yeah, here in Ohio we don't have to get emissions testing on cars that are 25 years or older, plus like Bonzo mentioned we can get a historical plate for under $20.00 which is valid for 50 years but the stipulation is that you don't drive the car as general transportation but more like to cruise-ins, parades, or sunny weather drives in the country. So unless the law changes, I'll never have to buy plates for my camaro again, which I think is pretty sweet. When I first learned of it, it sounded too good to be true and had me a little skeptical, because it's kind of rare for the government to help the car guys out, but they did in my case. Are you sure Delaware doesn't have some similar deal that's behind the scenes????

"HC (PPM) was 2113 (900 limit), CO (%) was 2.67 (9.00 limit)"


Sounds a lot like a lean misifre. Notice how high the CO limit allowed is, and how low your CO is.

I would turn the idle mixure screws out to richen it up some, but I would be using an infrared machine to do it. You could do it yourself by adjusting for highest idle vacuum, it would be guessing, but it's free.

Edit: "I had a local shop "TRY" to take care of this today. $100.00 out the window."

Do you mean it was adjusted and then retested/failed?

Actually...after looking at the paperwork the shop gave to me from the DMV the first curb idle test was a "BYPASS". The DMV computer just wouldn't accept the test. Yes, "FAILED". The shop tinkered with it, took it back to DMV the next day and it blew a 2113 HC but the CO passed at 2.67. Yes, "FAILED". And that isn't all that happened.

I work at night, so this guy calls me at 1 PM, wakes me up, and says one of the studs had backed out on the #2 cylinder and it would cost me a couple a hundred dollars to check the rest of the studs and repair if needed. The thing is, his shop did the work on my 186 heads. I asked him specifically to pull the pressed in studs and install the screw in studs with the small shoulder on them. I know this guy. We worked together in the Air Force in the 70's, so i wouldn't think he would f__K me. My wife seems to think that is what he was doing and I thought it odd myself. When I drove the car to him it was screaming. No ping, smooth as a babies behind but when I went to get it they all said it was running like crap and one of the studs pulled out. I asked him how can that be if they are screw in studs and you where the one who put them in. The car wasn't dropped off that way. I had to feather it home. 4.10's in the rear. I'm so p__SSED off right now that a friend I have known for 30 years would do this.

I pulled the valve covers when I got home this morning and checked the top end. I have yet to recheck the rocker stud in question but I will shortly.

The reason I'm doing this is so I can get Antique plates on my car. This way I won't have to take it in every 2 years for inspection and have to go thru this crap every time.


Anywho, I still need the experts help so I know what direction to go in. I might as well do it myself and gain some knowledge along the way and keep my $100.00 in my d_mn pocket.

:angry: :mad:

Can anyone help me here?

im a smog tech in CA and i need more than just HC and CO + CO2
we use HC, CO, CO2 and O2 all of which together give a much better picture of the problem, so if you have those numbers i might be more help

but just from the high HC and low CO it is lean

Can anyone help me here?

Hmmm, I thought I did.

Guess not.........

Maybe since I've only been doing emissions inspections for 25 years.

im a smog tech in CA and i need more than just HC and CO + CO2
we use HC, CO, CO2 and O2 all of which together give a much better picture of the problem, so if you have those numbers i might be more help

but just from the high HC and low CO it is lean



The sheet I have in front of me has:

Emissions Inspection Information - Curb Idle

HC (PPM) Reading = 2113 900 Limit(s) Fail
CO (%) Reading = 2.67 9.00 Limit(s) Pass
CO (%) + CO2 (%) = 9.58


That's all of it.

"HC (PPM) was 2113 (900 limit), CO (%) was 2.67 (9.00 limit)"


Sounds a lot like a lean misifre. Notice how high the CO limit allowed is, and how low your CO is.

I would turn the idle mixure screws out to richen it up some, but I would be using an infrared machine to do it. You could do it yourself by adjusting for highest idle vacuum, it would be guessing, but it's free.

Edit: "I had a local shop "TRY" to take care of this today. $100.00 out the window."

Do you mean it was adjusted and then retested/failed?


Sorry dude...No I had it backwards. When I looked at the paperwork again, first test bypassed the DMV's computer and wouldn't register a reading. On the retest after adjustments were made it blew a 2113 HC, 2.67 CO, and 9.58 CO + CO2 and failed.

I was confused still because I got an e-mail stating I was too rich and I should lean it out. I still need more info or at least what the majority says.

I did screw in the adjusting screws to make it lean but it still seemed like it wanted to burn my eyes.


Not sure what an infrared machine is.

:thumbsup:

Gary, if it has to pass, you're gonna need to find a shop with an old fashioned Sun tuneup machine, with a scope and an infrared sensor. Someone who's actually seen a mechanical distributor, carbed car this century

The sensor goes in the tailpipes and reads the exhaust gases, just as the smog tester does. The scope gives an accurate picture of how all 8 cylinders are actually firing.

With this info, the shop can determine the optimum timing and mixture to get the cleanest possible idle.

High HC and low CO combined indicate a lean idle mixture, lean enough to misfire and pass raw gas out the tailpipe. If the mix was rich, both would be high.

If you have to tune it yourself... set the idle speed high, 1200 rpm or more, to reduce the effects of cam overlap. Advance the timing enough so it sounds as smooth as possible. Adjust the idle mixture using a vacaum guage. Small equal adjustments on both screws, starting form a known point. Best to start lean so you know where you are, bottom the screws, turn em both out 3/4 turn. Then richen both in 1/8 turn increments until you get the highest idle vacaum, while also working the idle speed and timing to get the stablest possible idle.

Tuned like this, is will idle fast, probably ping at part throttle, and not be particularly driveable, but it should pass an idle sniffer test.

you dont need an emissions test only cars 24 years or newer :)

ok i seen a guy with same problem as you in delaware.

first he changed the oil and filter (yes you read it correctly)
he then tweaked the timing.
changed PCV
then bought a bottle of emmisions test passer in advance auto.
he passed with flying colors.
he also stated that he cleaned out the PCV hose of any oil before then test .
burning oil will make your numbers high.

ok i seen a guy with same problem as you in delaware.

first he changed the oil and filter (yes you read it correctly)
he then tweaked the timing.
changed PCV
then bought a bottle of emmisions test passer in advance auto.
he passed with flying colors.
he also stated that he cleaned out the PCV hose of any oil before then test .
burning oil will make your numbers high.


Everything is brand new...PCV, oil filter, oil, sparkplugs, etc. Engine is fresh, 3500 miles. I'm going to go with a 4777 650 dbl pump Holley instead of the 4053 that's on the engine now. The 4053 may be the problem since I haven't touched it yet and the 650 is new. Currently the timing is set at 12 degrees. Set at 9 degrees the engine pings badly when I put my foot in it.

you dont need an emissions test only cars 24 years or newer :)



Are you in Delaware? DMV emissions test cars from 1968 on.

mikemeg, don't assume all states have the same rules regarding emissions as they dont. It vary's from state to state.

From the DelDOT (http://www.dmv.de.gov/services/vehicle_services/faqs/ve_faqs_inspection.shtml) webpage:

"What vehicles require emissions testing?

Emissions tests are required on automobiles and on trucks with a manufacturer’s gross vehicle weight rating (MGVWR) of 8500 pounds or less. Exceptions include vehicles manufactured before 1968, diesel-fueled vehicles and motorcycles. DMV conducts approximately 400,000 tests each year."

Any progress Gary?

"Emissions Inspection Information - Curb Idle

HC (PPM) Reading = 2113 900 Limit(s) Fail
CO (%) Reading = 2.67 9.00 Limit(s) Pass
CO (%) + CO2 (%) = 9.58 "


Those readings mean it's LEAN, not rich.

Take the CO up to 4.00 or 5.00.

Those limits are very liberal, my state is much more strict.

Even if it is lean your HC number is very high. You should pass easily with that standard.

Use that new 650, put 64 or 65 jets in the primarys.

I have to deal with these standards: HC-400 PPM, CO- 3.5 idle & loaded

Good luck

Well I took the car in on Monday for a retest. I put the 650 DBL pumper on and both air/fuel mixture screws were already screwed out 2 full turns. I advanced the timing to around 14 to 16 degrees, which I think should have been retarded instead. I left with this on the printout:HC 1428, CO 5.25, and CO + CO2 13.81.



I have been e-mailing 400bird and getting some good info from him and checked out this website as well. http://www.bob2000.com/carb.htm



I still have 10 days to work on it. So any more help or guidance will be appreciated.