Need some Emissions help
 

Well it is time for emission test again on my '67 C-10. Last year when I went through I was right on the allowable for hydrocarbons and just under for CO. It was a little too close for comfort for me to go back again this year without trying to improve it a bit. So If you all can help me out with some suggestions I would appreciate it.
I have a '67 C-10 with a 350/400 combo. It has HEI, Performer intake with a 1406 edelbrock, no EGR, running at about 10* initial with 32* total timing. Idle is at about 700 in gear. The engine was a GM crate motor with about 6,000 miles on it, about 3,500 since last years emissions test. I just changed the oil, am running mobil one, and have a new air filter in it.
Thanks again, Andy

Bringing the base timing down will help with the HCs. Say set it a 4-6, adjust idle to about 700 and adjust the carb to match.

do they run it on the rollers or test at idle?

agree with kwmech. you can also change to the leaner metering rods that came with the 1406. CRC sells a products to run in your gasoline. I forget the name but it is some like " pass smog now". It seems to work for me and was suggested by a technician that repairs failed smoggers. The biggest difference you can make is change the oil and oil filter just before you go to have the test performed.
* change oil and filter
* reset timing
* 1406 metering rods
* CRC engine cleaner
* make sure your plugs are clean and set
* new or clean air cleaner

I have just about the same setup as you and I had to retard the timing way back so it just about ran and turn the idle mixture screws way in. It passed everytime. Now I have classic plates on it so I don't have to get it smogged anymore.

if your taking an idle test, adjust your idle rpm to the highest allowable during the test

Unfortunately they run it on rollers with a variable speed, so they have opportunity to stomp on the peddle, and they do. In fact, if they drive on the road like they drive on the rollers they would be terrors of road.
I also read last night that disconnecting the PCV valve from the air cleaner might improve emissions as well.
When adjusting the timing to 4-6 and setting the idle at 700, what is the best procedure of setting the carb? Do I just run the mixtures screws in till it stumbles and back it out just a hair?
Thanks again, Andy.

go to auto zone buy a 4 barrel adaptor 16.00
to a two barrel carb....
slap a two barrel on.....you will pass with flying colors.....
reinstall your four barrel......


trust me .....i did it cut every thing into half.......i am leving the two barrel on.......4 more miles per gal........