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Enrichen trasition circuit

midnightrider1818

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Question for the holley gurus, I have a 850 double pumper on a stock late model low compression 440, msd distributor and performer rpm intake, stock cam, when I cruise at 60 im running on the transition circuit and running lean, how would I go about enriching the transition circuit with keeping my idle afr good thanks
 
Just a picture for reference

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The cruise AFR is adjusted by the main jets, air bleeds etc. The main jets will have no affect on the idle circuit. The full throttle AFR is adjusted by the power valve restriction. This is of course over simplified.
 
He says his transition is lean. Transition fuel is supplied by the idle jet. Increase the idle jet in 0.002" increments & retest. Idle mixture gets RE-adjusted via the mixture screws.
You could also try raising the fuel level slightly about 0.100" before drilling any holes.
 
Need to test either without the air filter or the filter spaced higher away from the fuel bowl vents. If the air filter lid is too close the the bowl vents it can mess up the carb metering.
I think if you had a lean spot at tip-in in the transition then enlarging the Idle Feed Restriction (IFR) size would help, but you mentioned lean at 60 MPH in the transition circuit so I think using a smaller Idle Air Bleed should work better to richen the transition and quicken getting into the main circuit.
 
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