[Mellopar]

Whats going on , a few different ideas would help here folks. I have a 77 aspen with a warmed up 360 its got a bigger cam higher compression the whole deal, but the demon carb puked a while back and I replaced it with an edelbrock , since then it was running great, smooth pick up , nice idle, plenty of power. One night leaving work it started doing a breaking up type of thing at throttle under load, its fine in park and neutral but going it randomly breaks up, worse when its warm. The fuel pump is new the line is new the filter is new, the tank is fresh. The car seems to be almost like its running out of gas but is smelling rich at idle at the same time, I am starting to think its in the dizzy but am running out of patience with the driveability of it now. any ideas would be appreciated, I have checked and have zero vacuum leaks as well. And the squirters are coming on at the first move of the throttle.

 

[ImperialCrown]

If you sense a rich condition, you may want to pull a couple of spark plugs to make sure that the tips aren't showing signs of black carbon fouling. This can cause misfire. You might want to check the adjustment of idle mixture screws and floats (if there is an external adjustment), just slightly lean is good.
If this is a non-lean burn, you may want to try removing the vacuum advance hose from the distributor and plug it off then road test it for breaking up. If this clears it up, the pick up plate may be loose, worn or misaligned. The flexing of the pick up wires while the advance plate moves can also indicate internally broken pick up connector wires. Check the distributor shaft for play. Inspect the inside of the distributor cap for arc-marks or moisture
The secondary ignition including the ignition coil, distributor, cap and wires and spark plugs would be the first thing I would look at as the most likely trouble spot.

 

[AC TC]

i once had a dizzy that made the engine behave like it was
wery lean around 3000 rpm. Revving the engine made the spark go everywhere.
So definately... check your dizzy and other ignition parts before replacing the carb.

 

[Mellopar]

dizzy cap and rotor checked out Im going to check on the wires next something is definetly amiss I got on it on the highway and let off quick and the drivers side backfired slightly out the exhaust ...unburnt fuel is making me wonder .

 

[ImperialCrown]

Sounds like a rich idle adjustment if unburnt fuel ignited in the exhaust with a closed throttle on decel.
Does fuel drip from the venturis at idle? That may be floats too high or heavy.

 

[Mellopar]

to look at the carb its fine, like i said it ran fine for a good two months with this carb and then one day started doing this, all the plugs look good , if it was a bad wire the plug in question would be loaded. this makes zero sense, the car gets worse as it warms up and chugs almost like its not getting gas or spark and then it clears up at part throttle but if you get too heavy its all over again, the dizzy cap rotor plugs and fuel pump check out and its still giving me the finger. If i have it in park i can rev it dizzy if i power brake it it instantly starts almost chugging and cant even break the tires loose, the kicker is no smoke while it does it.

 

[Mellopar]

i talked to the tech line at Eddy and they said the top caps be pulled and check to make sure the springs were popping the rods up, they both are and everything looks fine and free moving, i drove home after work and the car was worse than ever.