Ok, I've posted another topic about this, but I can't seem to get it straight.
The Quadrajet is on a 1986 Chevy C10 (original carb). I rebuilt it, and since then I'm having this cold-start problem.
When I start it, it idles very rough and just kinda chug-chug as it idles. As it's idling, it's backfiring through the exhaust quite often. Not too loud, just a couple of firecrackers. Once I drive it, the problem goes away (since the motor is warming up).
To me, the backfiring tells me that it's too rich. I did, however, shorten the rod for the choke pull-off, and I think it made it worse (reduced the chock plate to airhorn gap from 1/8" to slightly under 3/32". It SEEMED to backfire more, but I wasn't sure.
Since it's been getting very cold here (below freezing during the morning), it's pretty tough to start the thing because of this problem. Almost wear the battery down trying to get it to start.
What do you guys think?
1969 Base Camaro
Vortec 355, Perf. RPM, Demon Carb., TH-400
All sheetmetal is NOS GM
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