carb spitting mixture back out, pushrod not in lifter bore, success inside! Options

[purple]

Hey guys, I have a bizarre problem with my engine. I'll give you guys some back story after describing the problem.

The engine runs, poorly, it sounds like it's running on 3 cylinders. And wonder of wonders, it IS! Cylinder #3 is doing something really weird. It's blowing all the air & fuel mixture out of the carb throat! the other 3 are drawing down just fine, but this one if i pull on the throttle the engine spins up a bit faster and it becomes a HUGE plume coming out of #3.It eventually ignites and makes a sick ass crack...not that i'm in to that kind of thing.

it's running at 150 degrees where the other 3 are likely 200 degrees higher. why is this happening?

I have a 2.0L (i think ) with 1.7L heads and I just put the weber 40 IDF's on there and set the timing as best as i could on the mallory unilite, which has run the engine well for a few miles. the engine also has a eurorace header and a hydraulic cam and lifters.

the rocker for cylinder #3 exhaust was kinda loose against the valve, and as i've read it's got to be in constant contact, so i adjsted it per webcam's specs.

Is it possible my intake valve on #3 isnt closing all the way, making all the compression go back up the carb throat? I'm kinda lost with what to do with a puking carb, i've never seen anything like this!

Thanks guys! please ask me questions to get closer to what's going on if you need info!