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Discussion Starter #1
I need some help tuning my carbs. Just went out today to mess with them to see if i could get them better. I did get it to idle down to 4000, turned the screws pretty far out though. Also turned by gas/air screws out to about 3 1/2. I looked at my manual and it says that if you need to turn the air gas mix out more than 2 1/2 then you need to get different needle or something, is this true? Should i think about getting different jets or needles? And how do you judge if it is running rich or lean? Im just doing it by smoke but i think thats wrong. When i was done fiddling with it i hhad it that when i started hitting the throttle it would bog for like a split second. Also, where should i start my idle screws at? I think they are mixed up now (not both at the same distance out).
 

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Nick,

First thing to do is make sure you have about 1/8" free play in your throttle cables at idle to assure that the throttle slides are not being hung up by them. Next, look inside the back of the carbs and back out the idle speed stop screws until the slides just stop lowering then recheck throttle cable free play once more. Once that step is established you can set up your idle speed by turning the slide stop screws (the ones on the side in line with the throttle bore) until the slides just start to move up wards. Adjust them by 1/2 turn increments one carb then the other. The other adjustment (brass idle mixture screw should be set at whatever your manual says and not deviated too far from. If the idle stops are adjusted correctly and you need to open the idle mixture screws more than 3 & 1/2 turns open then you need a larger Pilot jet inside the carb. Most 4500 (377 engines) with dual 30 MM Mikunis have 45 to 50 sized Pilot jets while the single carb units have size 30 Pilot jets. Set a base line first then deviate. If these carbs were the stock 1980 Citation SS carbs then they shouldn't be too far off the mark.
 

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Discussion Starter #3
they are gonna be off because they needed a rebuild, so i did. And i know they were adjusted from the stock. I may try that today. I did set the mixture screw at 2 1/2 turns out before i messed with it but i didnt know what to do with idle screw so i left it.
 

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Discussion Starter #4
I went out today to go mess with them again because its a little bit colder. When i screwed my air screws in all the way in they went in different amounts. Heres some pics. Is this alright? Are they different sizes? Im not sure here so i need help. It looks like the left side is out more than the right.



Right


Left
 
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