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Discussion Starter · #1 ·
i changed my intake and carb to a rpm air gap and 750 holley. now when i floor the pedal it studders. also when im at a stop light you can feel the motor shake and studder. i was thinking it might be that it needs more fuel or timed. any help would be appreciated thanks!
 

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What is the static timing set to and total timing? Is the carb new out of the box? Which model? Is the engine all stock?
 

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Discussion Starter · #5 ·
What is the static timing set to and total timing? Is the carb new out of the box? Which model? Is the engine all stock?
idk the timing but i had the timing set before i changed the intake and carb. im going to check timing today though. the carb is new and the holley 750cfm mechanical choke. engine is all stock.
 

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Many things can make a motor shutter and act like that and one of the biggest things that make carb tuning almost an impossible task is when the timing is not set up correctly for the engine build that sits under ones hood and I always take a piece of paper and write down everything down on the carb such as how many turns I can turn the primary screw before more than .040 of the transfer slot is showing so like that I don't have it opened up to much to the point the engine is idling off the transfer slot and not the idle discharge ports and thus making the idle mixture screws almost non functional.

I put down all the specs of what size jets I am starting with and how many turns on the primary idle screw and also write down the same on how much the secondary side is open up as well and a good place to start off on that is about half a turn past contact and putdown where your float setting is at etc. I write everything down so like that as I am tuning if something does not seem write or run right I go back to my notes and write down what the change did and what the response was.

Verify timing before anything else and also check to make sure your ignition system is up to code with good spark and good plug wires and a good working distributor of what ever style your using such as an old points type or a hei or a more modern type. After that is all said and done when I go to setup something I start with the timing and then double check everything else and then get the engine started up and running.

I start off with the idle and off idle and after it's done I then go on to the accelerator pump shot and shooter size tuning. I then go on to main jetting and after that is good I then work on the secondary side of things and would recommend either a holley quick change kit which has the different color springs for different opening rates or the quick fuel adjustable vacuum pod which comes with a purple spring installed and all you have to do is just turn the screw on it like you would a idle mixture screw and it adjusts the sensitivity on how quickly the secondary side responds and you can also use a different color spring in it if you want but unlike the holley one you have to take the whole thing off.

Other things could play into effect as well and full engine specs if you know them along with vehicle and transmission etc would also help as many other good folks on here know a lot more then I do but am learning every post made.
 
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