Spark plug color

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ChuckN

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@Matt69olds the one thing that is perplexing is that otherwise it runs fantastic. Start up, cruising, in traffic, it’s flawless. It just seems to have a transitional problem between the accelerator pump and the main circuit between 1000-1500. Everywhere else, I could drive it as is and never want to touch a thing.
 

Matt69olds

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Have you tried going leaner on the pump shot? Just a thought. I’m sure there are ways to tailor the accelerator pump to almost any engine.
 

ChuckN

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Have you tried going leaner on the pump shot? Just a thought. I’m sure there are ways to tailor the accelerator pump to almost any engine.
For sure. Next good day I’m going to play with that. I’m stuck on the assumption that it’s getting not enough fuel, could always be the opposite.
 

potent rodent

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that plug shows its lean, put the silver spring in it and go from there
 

MikeB

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I have seen more timing advance cure a low RPM stumble on at least two engines with Edelbrock carbs. For example, if you're at 10 degrees, try 14. And double check everywhere for vacuum leaks.
 

ChuckN

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Ok, today I got it nice and warm. I manipulated the accelerator pump arm to make it a little more aggressive, and then put in the silver springs. What an improvement! Still has a very occasional stutter with a “braap “ moment, but wayyyy better. Might go up one more step on the Edelbrock algorithm.
 

ChuckN

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Silver Edelbrock springs installed. No more stutter, plugs look good. Been enjoying driving her around, sitting in traffic, opening her up, going wherever and doing whatever. Doesn’t seem to complain. Who knows, this could be my goin’ to town rig and daily driver.
 

84GMCSierra

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I printed one of these out to keep in my 84 GMC.
 

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potent rodent

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go with the silver spring it cured my stumble
 

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