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Any good tips on leaning out a 1050 Alky Dominator? It's too rich at idle but leaning out the idle mixture screws leaves a bad transition from staged to full throttle.
 

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Is it 2 circuit or 3 circuit? If 3 circuit, try pulling the intermediate air bleeds if adjustable. Does it have transfer slot restrictors in the main body and what size is the transfer slot orifice? Might want .055". (I have a set of billet blue alcohol metering blocks if you want some.) If you need some good advise, go to the fuelsytemforum.com.
 

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It's a 2 circuit unit. And I'll have to tear it back apart to get the other info. I tried looking for that forum (even with a spelling change) and that's a no-go. Thanks tho!
 

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been working on mine for some time now..same issue. I could write a fucking book on the subject. But in short how much do you need to lean idle? Is it seriously fouling plugs? Agree key question 2 or 3 circuit? Slight rich, definately air bleeds is the way to go, mine was stupid rich and I've now changed air bleeds, IFRs, Emulsion restrictors and of course re-jetted and toyed with power valves (although they are back to out of the box now). I've got my idle cleaned up pretty nice now and tuning to get rid of off idle hesitation and richer WOT now. Note I had lots of people talk to me about drilling the throttle blades and T slot restrictors both of which I was super reluctant to do for fear of fucking up the carb.
 

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No carb guru but air bleeds?
My question on that is are air bleeds drill size? Someone else suggested opening up the idle air bleed from 39 to 50 but I'm not clear on if that is a 39 to 50 drill size or the actual hole diameter.
 

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been working on mine for some time now..same issue. I could write a fucking book on the subject. But in short how much do you need to lean idle? Is it seriously fouling plugs? Agree key question 2 or 3 circuit? Slight lean, definately air bleeds is the way to go, mine was stupid lean and I've now changed air bleeds, IFRs, Emulsion restrictors and of course re-jetted and toyed with power valves (although they are back to out of the box now). I've got my idle cleaned up pretty nice now and tuning to get rid of off idle hesitation and richer WOT now. Note I had lots of people talk to me about drilling the throttle blades and T slot restrictors both of which I was super reluctant to do for fear of fucking up the carb.
Right there with you on those mods - thought about it but backed off not wanting to ruin parts. Idle wise, it's rich to the point of being stupid. And the plugs look washed and maybe too cold. I want to try a step hotter but the major problem around here is that we have one track open, it's hotter than blazes and there's no TnT sessions - and I hate going to a race and trying to test.
 

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yep..been there. Hotter, colder made no difference. I was so rich I had unburnt fuel spitting out the exhaust pipes. Read my Speed-talk thread. Some great advice from those there, but honestly, while the air bleeds helped, it wasn't really till I got into the IFR's that it made a big difference to my idle mixture (cleaned up)
 

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racingfuelsystems.com is the site. I was just on it. Also look up jmarkaudio/Mark Whitener. He is on that site. He helped me understand fuel curves and supplied me some parts.

Idle air bleeds usually can go up or down 10 (.010") orifice sizes to see a real change. 2 circuit is better for alcohol, so you are good there. Also Mark W really pushes having the idle restrictor in the "lower position" to get better control of the idle circuit.

It is too bad that Holley puts out Dominator carbs with stupid calibrations. Even some custom builders don't do transfer slot restricters or lower the idle fuel restricters. Any carb without replaceable idle and high air bleeds is not a custom carb in my opinion.
 

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.039 idle air bleed in an alky carb is just stupid...
Find out what idle feed restrictor are for size, also make sure you're not too far into the transfer slots, both front and back blades need to be the same....
2 or 3 circuit has no bearing on it being pig rich....
Drill the idle air bleeds out to .060 to start....
 

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So it seems.

Why would QF build carbs this far off then? So you spend more money on it or is just a lazy ass situation where they let the consumer deal with the problems?
They want it to run on anything....so they cover their asses with tune ups that'll run...
You better get it leaned out before you fuel wash the rings.
 

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Alcohol is forgiving when rich, 1 carbon atom per molecule doesn't foul plugs like gas. What engine is it on?

 
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