221 cui stumble and backfire

I also rebuilt the fuelpump with new diaphram - it was a complete kit.
Pressure is fine.

I ran the car with the same Holley 94 carb before the engine rebuilt.
I noticed the hole in the carb base but its blocked off by the gasket/manifold.
Would hate to have to spend another 300$ on a new Stromberg carb.

Im not using the stock coil setup but instead a separate coil and distributor kit.
All new.
 
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If using the coil adapter, the tube type coil is probably built with an internal resistor. You won't need the stock resistor (under the dash), so it will need to be disconnected.
I recently went back to a rebuilt stock coil and condenser after several attempts at getting a coil adapter, "new" coil and "new" condenser to function properly. Skip Haney did the coil and the condenser came from Bubba.
 
TDS said:
I also rebuilt the fuelpump with new diaphram - it was a complete kit.
Pressure is fine.

Hey again: Just to let you know: I rebuild my fuelpump - but some misfire continued. Though it seamed to work - it didnt deliver properly. Today I put in brand new pump - and problems are gone.:D
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Like Scinla said , (bad accel pump or lean condition) Check that the Rubber or should be leather plunger is not compressing on the spring ,Ted
 
"Thought it was just a car backfiring..." this observation usually comes from someone too young to have actually ever heard a car backfire...
 
Cleaned and checked vacuum connection.

Sparkplugs are covered in black sod except from number 7 and 8. They are wet and properly not working or not getting a spark.
Left bank is not as hot as the right bank.

Am I running to rich due to the black plugs?
I got a set of 0.048 jets.
 
Replaced sparkplug 7 and 8.
Will take rpm now but now I got a lot of popping out of the exhaust.
I'm using Champion D16 plugs actually not great as I need to replace them quite regularly.
What can cause the popping ?
 
Have you swapped on a known good coil and or condenser. I mean one's that run great NOW on another car. Not an "it worked ok back along" have you checked spark intensity? An easy 3/8" off the block and rev the engine up and keep a strong blue spark on each plug one at a time. Did you check coil input voltage? When this stuff is all good, you can concentrate on the fuel side.
Martin.
 
TDS, go back and read the clues in your posts.
Rebuilt distributor, carb and fuel pump. Ran a #94 before without problems. Back fires through exhaust, Sooty and wet plugs. Unequal spark to all plugs.
New after market condenser coil and adapter.
I would do as Scooder suggests in post #29.
 
I agree, listen to Scooder. From my experience, when there is a pop in the exhaust, it's usually related to an on/off ignition issue.

Sal
 
After fire can happen from a leaky carb (power valve? loose jet?), intermittent spark (not allowing full burn), or a leaky exhaust valve (not allowing combustion). A compression check will tell on a valve problem. A stuck, bent, or burned exhaust valve can happen anytime. Folks have pretty well covered the other items already.
 
Again
FlatheadTed said:
Run the revs up with one wire 1/4 -3/8 from the head ,if it turns from blue to a weak yellow spark then its a ignition problem .If it runs better with your foot flat to the floor or the choke out a little its a fuel problem ,possible dirt in jets ,Pump ,or blocked line ,vacume leak .Pull the carb top to see were the level is .Ted
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