engine wont start

[jcondo]

My fathers plow truck has been having some issues lately. Its a 79 with a 400 sbc but I don't know the year of the engine, its been 20+ years since I installed it.
I got it running enuff to pull into the shop and replaced the hot air choke on the carb with an electric upgrade kit. Had it running good afterwards and backed it out, plowed a bit of snow in front of the shop, maybe 20 mins of running time. Then put it back in the shop and worked on another truck I have.
Today I went in to see if the choke was gonna be closed and would open back up like its supposed to, and it wouldn't start up. It turns over and has fuel to the carb but just wont fire. I had a poof of smoke come out of the carb and thought well maybe the carb is messed up cuz its over 20 years since it was redone. I took my edelbrock off my 1980 Malibu that I know runs and put it on the plow truck.
It is doing the same thing minus the poofing of smoke out of the carb. If I manually move the throttle linkage I can see gas going into the carb so I don't think its a fuel pump or filter issue.
What else could be my issue?
We have done nothing to the engine electronically or mechanically for it to not run. Fuel pump in mechanical and I took the quadrajet off because the oem gas line had been jb weled and was loose, so I couldn't put it back on, is why I put the edelbrock on.