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Old 11-29-2023, 10:08 PM
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shaker455 shaker455 is offline
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Quote:
Originally Posted by TransAm 474 View Post
Thanks Shaker, so basically you are saying that after coming out with the mixture screws to achieve highest idle, they may have to be adjusted out even further to increase the mixture even more, even though it might lose Idle RPM slightly? Sorry, I am not trying to question you at all, just trying to get a good understanding

....and the Idle Bypass Air, I have no idea how much this carb has, as SMI didn't give me any specifics on the carb at all, but I do know you can pull a small manifold vacuum hose off while it is idling,
and it does really affect the idle RPM much at all in either direction,
but would that be telling me if it needs more Idle Bypass Air or not? Does that test work the same as adding more Idle Bypass Air? Can one simply add Idle Bypass by drilling the primary blades? If so, what size hole would you recommend starting with? Of course, I wouldn't do that, unless it comes down to knowing that is for sure what it needs. Thanks for the help
Can you say again what happens when you unplug a vacuum source when idling?
Idle picks up a lot or no real change?
Do you have a digital tach on your timing light?
You should pull the carb off and make sure choke is fully open and no fast idle contact, make sure idle speed screw is in contact with throttle shaft and look and post a pic of how far open your blades are @ idle.
Don't drill anything at this point, gather calibration sizes like bypass air hole size in base.

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