454 spits out carb at 20% or so throttle at low speed

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UNEAKMEDIA

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At take off at about 20% throttle it seems to bog a little then spit out the carb. If I blip the throttle it'll get better and take off. Seems like its lean. Never has this issue when I get on it with more throttle. Where should I make this adjustment? Air fuel screws on the front of the Edelbrock 1411 Performer series? The truck also has HEI and was bored 30 over with an RV cam. I just rebuilt the carb changed the spark plugs and cleaned the points to try to solve this. I thought the carb rebuild would have fixed it as most of the jets and ports were clogged. I'll include some pictures and maybe someone can help.
That was the plug from cylinder 1. The rest were not nearly as bad. They were a bit white.
Thank You.
 

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MarineOne

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Sounds like a lean pop but that could be there's still clogs. Try letting it run and snuffing it out by jamming rag over carb. Vacuum goes real high and usually pulls any junk out of carb.

Could also be intake leak causing un metered air.

Also accelerator pump / seal could be bad. If you tip into throttle really slow does it pop?

Did you bore scope cylinders? I've had carbon build up cause a pop too
 

UNEAKMEDIA

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Accelerator pump is brand new. I'll try moving it to squirt more and i'll scope the cylinders tomorrow morning. Thanks MarineOne
 

fast 99

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By spitting are you saying backfire?
 

UNEAKMEDIA

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out of the carb not the exhaust. and sometimes it diesels when i turn it off. not so much after the rebuild. i'll have a chance to work on the truck this afternoon and i'll post the results. it sounds like a pop not really loud but it kills the engine for a split second and it continues to run.
 

AyWoSch Motors

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Sounds like timing
 

WP29P4A

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I was thinking timing or firing order. I have also had a dist cap with a hair line crack cause random firing issues.
 

UNEAKMEDIA

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I was thinking timing or firing order. I have also had a dist cap with a hair line crack cause random firing issues.
timing is at 8 degrees at idle. I'll look over the cap again. I'll also make sure my plug wires arent touching anything or each other.
 

UNEAKMEDIA

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ok so i was looking at the firing order diagram and according to the diagram my plugs are not in the correct position in comparison to the connector. so i switched them to match the diagram online and it was completely wrong. is it possible that the distributor was stabbed in 180 degrees? if so should i remove it and put it back in the correct way?
 

UNEAKMEDIA

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did some research online and learned the distributor can be facing any direction as long as the 1 wire goes to the point at tdc. doing that now.
 

UNEAKMEDIA

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I'm a newb so things like this are bound to happen. I would just rather learn how to fix things myself. Even if it requires me to screw some things up.
 

UNEAKMEDIA

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so there is a little carbon on the piston but not much. and the distributor seems to be in great shape. it also seems to vary in rpm when i'm cruising like 50rpm i notice a 1-2mph change. maybe its a vacuum leak somewhere? I'll spray around with some carb cleaner today and see if i can find any leaks.
 

Knuck55

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Not sure of the guts of the edelbrock but I would start with 12 degrees on the timing and possible look at the intermediate circuit in the carb. Possibly move up a jet size if that is what is in it. Hope this helps.
 

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