AZ emissions on a 392 with auto HELP ME ASAP!!! - Off-Road Forums & Discussion Groups
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post #1 of (permalink) Old 05-13-2004, 08:57 PM Thread Starter
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AZ emissions on a 392 with auto HELP ME ASAP!!!

I have a 1972 Travelall 2wd with a 392 and 3spd auto
I failed emissions, and I purchased a new edelbrock 1404 [500CFM].
It improved the results, but still failed.
here are my results:
Loaded Reading/Loaded standard -- Idle reading/Idle standard
HC[in PPM] 209/400 -- 313/400
CO in % 6.27/3.75 -- 5.79/5.00

I currently have the vacuum advance on the Ported vacuum port on the carb. it seems to have a bit better throttle response with that connected to direct manifold vacuum as opposed to where it is now, on the ported portDo you think it will have better results if my vacuum advance is active at idle, as opposed to how it is now, on the ported port on the carb?
I have not touched the idle mixture screws since taking the carb out of the box, so they may be too rich.
If i try wide open throttle, from a dead stop or from 5mph, it consistently hesitates, like a vr-vr-vr-vroom, until I ease off the gas. If I floor the gas at a cruise, from like 30MPH, it downshifts and accelerates perfect.
Would that hesitating be the auto tranny, or is the carb just still too rich??
I tried to set timing with a vacuum guage [very improper, I know] since I cant afford a timing light right now. the way I went about that is to rotate the distributor until the vacuum reaches the highest readout, then rotated the opposite direction until the vacuum went down by about 1 in/Hg.
Please advise on what I can try, I still have like 90 minutes until the emissions station closes!!
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